56 Replies Latest reply on Mar 5, 2015 7:12 AM by adtn99

    Telnet not working?

    ronnieb New Member

      For some reason I can't telnet into any of my Muxs anymore is there a fix for this? I rebooted one and could telnet for a week or two but then it stopped workig.

        • Re: Telnet not working?
          adtn99 Employee

          ronnieb,

           

          The first thing to check is the version of software your controller modules are running.  Version 3.42A is the current version of software and it is available via our website.

           

          If your MX2800 Controller Modules are running 3.42A then I need a more detalied description of your remote management architecture i.e. IP, Dial up Modem, etc, etc.

           

          rfox

          • Re: Telnet not working?
            jbell New Member

            We are experiencing the same thing with 3.42a and a couple of other versions.  Telnet sessions (IP) are unsuccessful after a few days.  If you go into the administration via RS-232 and remove the IP address from the management port, save, and then re-add the address and save, it works again for a few days - then stops responding.

             

            We really need to get this working.  Our NOC logs in to check the status, and after a few days they are unsuccessful.

             

            Message was edited by: jbell

              • Re: Telnet not working?
                adtn99 Employee

                jbell,

                 

                jayh's suggestions are a good place to start!  Please describe in detail what is meant by "Our NOC logs in to check the status" i.e. are they using some sort of automated process?  Are the MX2800s in question being managed via a private or public IP network?  Is it possible the IP network being utilized has recently added some sort of automated security scan program?

                 

                Recently I've handled a couple of calls that turned out to be the IP network using an automated security scan program that would lock up the Telnet port.  If so, there are two ways to resolve the issue.  Have the IP network administrator delete the MX2800s IP addresses from the security scan list or you can enable the IP Security option of the MX2800 to accept login requests from a select limited number of IP addresses.

                  • Re: Telnet not working?
                    jbell New Member

                    It's a private network, and they login via telnet periodically manually.  However, we have two systems that ping devices - including the MX2800's - one every 15 minutes and the other every 5 minutes.  and report failures.  Are we essentially to understand that pinging on a periodic basis may be causing issues for the MX2800?

                      • Re: Telnet not working?
                        adtn99 Employee

                        jbell,

                         

                        I performed multiple pings on our lab MX2800 and successuflly logged in via telnet without any trouble.  Next time the condition occurs try the following test.  Disconnect the IP network from the MX2800 LAN port and use a Laptop with a crossover cable attached to the LAN port and try initiating a Telnet session locally.  If that works it maybe something in the IP network.  If not, then well need to take a closer look at the MX2800.

                          • Re: Telnet not working?
                            ronnieb New Member

                            For some reason that didn’t work  but after more troubleshooting there were no Host IPs under system security options. Don’t know why it worked before and then all of the sudden stopped.

                             

                            Thanks for your help!

                              • Re: Telnet not working?
                                jayh Hall_of_Fame

                                There don't need to be IPs there.  That is only needed if you want to restrict access to certain hosts.  In our network, we limit control-plane and management via an external firewall and authenticated private network eliminating the need to deal with those settings.

                                 

                                If you have the MX2800 on the public Internet, then you absolutely want to lock it down with allowed host IPs.  Without SSH capability, I would strongly recommend against connecting the Ethernet interface of the MX2800 to the public Internet.

                                 

                                It would be nice if the MX2800 supported SSH as well as CIDR notation on the host IP form, but it doesn't so be careful out there.

                                 

                                Also, set the timeout to something reasonable and encourage your staff to gracefully exit telnet sessions with the logout menu commands, as well as following the logout steps with an expect script on any automated processes.  There are a limited number of telnet sessions supported, and if I recall correctly the limit may be one.

                                 

                                Another possibility, if you're going through a NAT or firewall with a low TCP timeout setting and someone stays idle for a while, the telnet session may drop without sending a RST to the MX2800 resulting in a wedged session.

                                • Re: Telnet not working?
                                  adtn99 Employee

                                  ronnieb,

                                   

                                  jayh's response & suggestions are correct!  We've performed multiple pings to our MX2800 lab units and we've not experienced a single telnet login failure!

                                    • Re: Telnet not working?
                                      ronnieb New Member

                                      I agree as well. I could ping the box just fine but could not telnet to it. Also the crossover cable from my Ethernet port to the LAN port on the box did not allow me access either.

                                        • Re: Telnet not working?
                                          adtn99 Employee

                                          ronnieb,

                                           

                                          Sounds like the unit's telnet session port is hung up.  If the MX2800 system in question is redundantly equipped (2 controller modules) I suggest you perform a manual controller card switch (you will have to remove the front cover/one screw to gain access to the controller modules on the right one on top of the other).  Physically remove/replace the controller module with the DS1 LEDs that are on i.e. this is the module carrying the traffic and providing telnet access this will force the traffic to the redundant controller module.  This should allow you to access the unit make the changes jayh shared and then you can see if that resolves your intermittent loss of telnet access.  Service wise this is a high speed traffic switch, but the users will take a hit so you may have to wait until your maintenance window.  Naturally if the system is non redundant there will be a service interruption to the end users.

                                          • Re: Telnet not working?
                                            adtn99 Employee

                                            ronnieb,

                                             

                                            I may have misunderstood one of your previous replys?  Are you saying the unit in question no longer had an IP address provisioned into it? 

                                              • Re: Telnet not working?
                                                ronnieb New Member

                                                In the System Security option portion(option 12) of the System Management Configuration page. Like I said before I could pong the box just not Telnet to it.

                                                  • Re: Telnet not working?
                                                    adtn99 Employee

                                                    ronnieb,

                                                     

                                                    If you enabled IP Security then you must populate the IP Host entries with the IPs that you'd like to have access to the system.  Perhaps you should open a technical support ticket 800-726-8663 and we can work directly with one another to resolve your issue.

                                          • Re: Telnet not working?
                                            jbell New Member

                                            I went in on both of ours and re-flashed them with the latest version again.  They are - so far - operating normally.  I'm hoping that resolved that issue, at least I'm keeping my fingers crossed.

                                              • Re: Telnet not working?
                                                jbell New Member

                                                Well, they have the latest firmware and have, once again, failed to respond to Telnet connections.  They are responding to pings.

                                                 

                                                Adtran, any ideas what else could cause this on these units?

                                                 


                                                  • Re: Telnet not working?
                                                    adtn99 Employee

                                                    jbell,

                                                     

                                                    Are you sure the IP Network Manager hasn't instituted some sort of security program i.e. one that tries to access/login to anything connected to the IP Network?  I'm assuming of course that you've made the appropriate auto logoff changes suggested previously and making sure all users who have access to the MX2800s are logging off gracefully after logging into these units.  If so, then I'd like to work with you direct to set IP security on one of these MX2800s i.e. restrict access to the target MX2800 to one IP address like yours only and see what happens over the course of two or three weeks.

                                                      • Re: Telnet not working?
                                                        jbell New Member

                                                        We have implemented everything else, but in our environment the IP security will not fly.  I need to access them, our NOC technicians need to have access to them, our IT manager, and two other people.  As we have DHCP addresses on our internal LAN, management of this feature would be impractical.

                                                         

                                                        As you can see below, there is another person having exactly the same issue, so something else is up.  We will be needing several more of these in the coming year, and the CAC WideBank 28 (now owned by Telmar Network Technologies) may end up being our choice if I can't get these working reliably for us.

                                          • Re: Telnet not working?
                                            cbh New Member

                                            Hello. I have 2 separate (Active/Standby) MX 2800 units and they both have the same problem of no telnet response after a period of no access. I manually have to power cycle the boxes to get them to start responding again. I am able to ping them at all times.  We do not have any network security devices that are blocking access. They simply stop responding to telnet requests after a period of time.

                                            Below is the version information.

                                             

                                            Code Version = 3.42A              

                                            │    Code Checksum = 1F5F                          

                                            │    Boot Version = 2.20A                            

                                            │    Boot Checksum = 0820

                                              • Re: Telnet not working?
                                                jbell New Member

                                                We are having the same issue, so I'm glad I'm not alone.  One thing you might find works versus power-cycling the boxes is to go in RS-232 and remove the IP address from the box (menu 3-3-1), save the config, then add the IP address back in and save the config.  That usually brings it back up and saves power-cycling, at least for us.

                                                 

                                                It has also been recommended that the 3-3-9 (Terminal Timeout) be set to a reasonable value.  We just went in and set that to 60 minutes this last Saturday.  I'm hoping it fixes it, but the last time with just the latest FW upgrade to the same config you are running they went about 2 weeks and Telnet stopped responding.

                                                 

                                                I'd really love to see Adtran fix this, as we are looking to buy several more MUX units in the next year and it's a choice between these and the CAC WideBank 28's (which are now owned by Telmar Network Technologies).


                                                  • Re: Telnet not working?
                                                    adtn99 Employee

                                                    jbell we are suggesting the use of IP Security/IP Hosts option to determine whether or not the LAN/IP Network is the cause of the issue!  ADTRAN can't trouble shoot IP networks.  Also we recommend a Terminal Time Out option of 1 or 5 minutes as a means of quickly determining the Telnet port isn't being locked up due to improper session termination i.e. the currently logged in user not logging off of the unit via the menus.

                                                     

                                                    When access is lost we also request the customer secure a crossover cable to access the MX2800 locally via the LAN interface before performing power cycles or controller module protection switching in an effort to isolate the source of the issue.  The online controller module carrying the traffic also controls the remote access if a protection has been performed previously then both modules have been tried.  Its possible the LAN interface of the chassis might have an issue, but we must perform the necessary trouble shooting steps before we can go there.

                                                      • Re: Telnet not working?
                                                        jbell New Member

                                                        In our environment we have both Change Control processes and Incident Management and Disaster Recovery requirements that make adding the IP security effectively impossible.  Our NOC must be able to access devices 24/7/365, and with DHCP addresses, I can't guarantee what they will have when they try to get in.

                                                         

                                                        Just to implement the session timeout feature in the firmware took a change control process with 5 sheets of paper, two meetings, and a presentation before a group of 6 managers and the CIO before it was approved, and it had to be done during a weekend night maintenance window.  Upgrading the firmware itself in a prior window took 6 sheets of paper, etc.

                                                         

                                                        In previous jobs, I could have implemented your request in about 5 minutes with no issues, but here there are a host of roadblocks to doing anything of this nature.

                                                         

                                                        As I mentioned, we found that going into menu 3-3-1, removing the ip address and saving, then going right back into 3-3-1 and adding the same address back and saving resolves the issue without power cycling or failover switching.  I have also failed the unit over to the backup card, and had the same telnet lockout eventually happen on each card.  Does that provide any additional insight?

                                                         

                                                        We have devices from a host of manufacturers on our LAN.  I just double checked with our NOC and Network Engineering groups.  This is the only chronic Telnet issue at this time.

                                                          • Re: Telnet not working?
                                                            adtn99 Employee

                                                            The fact the IP addresses are still there when you access the unit via the local craft port and erase/repopulate them as well as trying both controller modules indicate it's not a controller module issue.  What about using a crossover cable/laptop to access locally via the LAN/IP interface of one of the MX2800s instead of the craftport?  I appreciate your situation in regards to your network/management, but the steps performed up to this point haven't eliminated the LAN/IP Network as the source of the issue even though you have more than one MX2800 exhibiting the issue, how many do you have with the issue?  There are thousands of MX2800s deployed worldwide and managed via both public and private LAN/IP networks without any issues.

                                                             

                                                            The MX2800 is a mature product that hasn't undergone any major changes for approximately 5 years.

                                                             

                                                            I also recommend you contact ADTRAN TECH SUPPORT 800-726-8663 and open a ticket and I will be happy to work with you direct to discover the root cause of the issue.

                                                      • Re: Telnet not working?
                                                        adtn99 Employee

                                                        Code Version 3.42A is the latest released software for the MX2800.  This "Telnet issue not working after a period of time" started about 5 months ago and a handful of customers admitted their IT Depts instituted some sort of security program.  We instructed these customers to enable IP Security option/IP Hosts (IPs the MX2800 will allow a login prompt) and this resolved the issue for those customers.  Therefore we now recommend all customers with this issue use IP Security option/IP Hosts to see it will resolve the issue for them.

                                                         

                                                        We also recommend setting the Terminal Time Out option to 1 or 5 minutes.

                                                         

                                                        We also recommend MX2800 customers secure a crossover LAN cable to try establishing a Telnet session locally by removing the LAN cable from the LAN interface and connecting a Laptop locally via the crossover LAN cable before power cycling the unit or forcing a controller module switch.  This test will eliminate the LAN/IP as a possible source of the issue.

                                                         

                                                        If the issue continues to persist after performing controller module switching (the online load carrying controller module also provides the management access) then it's possible the Chassis Lan connection might have an issue.

                                                         


                                                          • Re: Telnet not working?
                                                            cbh New Member

                                                            Hi adtn99 and everyone else,

                                                             

                                                            I have set my timeout to 1 minute and let it timeout while I'm logged in for about 6 or 8 times now. I am able to get back in each time. I think that rules out the timeout being the issue.

                                                            I'll have to wait until I lose access to the boxes before I can try the crossover cable. When a unit stops responding, I'll remove / replug the LAN cable. If I still can't get into it, I'll try the crossover cable.  Fortunately, I'm the only person that accesses the 2800 here and I have one that's not in production, so I can take the lead on troubleshooting. I'm not sure how long it takes to lose connectivity and I also don't know if periodic attempts to access the unit resets the issue. This may take some time.

                                                            I'll let everyone know the next time I get locked out.

                                                              • Re: Telnet not working?
                                                                adtn99 Employee

                                                                Thanks cbh!

                                                                 

                                                                I access MX2800s in our support Lab almost every day and week without an issue.  We've even tried multiple pings to the unit to see if that would cause Telnet issues and they did not!  There are literally thousands of MX2800 deployed around the world that are managed via IP/Telnet without any issues.  Something is up, but we have to determine for sure if it is the MX2800 or the LAN/IP Network connection.

                                                                  • Re: Telnet not working?
                                                                    cbh New Member

                                                                    Agreed. I'll advise as things progress.

                                                                      • Re: Telnet not working?
                                                                        adtn99 Employee

                                                                        Thanks again cbh!

                                                                          • Re: Telnet not working?
                                                                            cbh New Member

                                                                            I have been in and out of my Adtrans over the past 3 weeks or so without a problem. However, today I cannot access either one of them via telnet. Per your suggestion, I connected directly into the units with a laptop and a cross over cable, but I still was unable to telnet into them. Pings returned just fine.

                                                                            I have not rebooted them yet, so if you would like me to try other things, let me know.

                                                                              • Re: Telnet not working?
                                                                                adtn99 Employee

                                                                                Cbh,

                                                                                 

                                                                                Don't perform a re-boot or controller module switch yet!  Can you confirm by visual inspection the traffic is running on the same controller modules you've been accessing for the past three weeks?  I'm trying to confirm there hasn't been a controller module switch?

                                                                                 

                                                                                If possible please provide the S/N#s of your Controller Module and their slot assignment.  If you don't have this information handy from your access activity the past three weeks that's ok.

                                                                                 

                                                                                I request you call 800-726-8663 and open a Tech Support Ticket so I can contact you direct.

                                                                                 

                                                                                Thanks,

                                                                                R. Fox

                                                                                  • Re: Telnet not working?
                                                                                    cbh New Member

                                                                                    I can confirm that the same controller modules (A) are still the ones that have been active for some time now. There has been no switch.

                                                                                    I don’t have access to the serial numbers of the controller cards because I can’t access the unit. Are they written on the outside of the MUX? If so, I’ll make another trip out there and write them down.

                                                                                     

                                                                                    I have attached the requested Wireshark traces.

                                                                                     

                                                                                    As far as a case is concerned, what information will I need to open a ticket? Let me know and I’ll get it together to open up a case.

                                                                                     

                                                                                     

                                                                                     

                                                                                    Charles Harrison

                                                                                    Sr. Telecommunications Analyst | XTO Energy

                                                                                    Desk: 817-885-1648 Cell: 817-201-2794

                                                                                      • Re: Telnet not working?
                                                                                        adtn99 Employee

                                                                                        Cbh,

                                                                                         

                                                                                        I understand about the S/N#s, I just thought you may have written them down or had a previous screen capture of them.  You can't secure the S/N#s without removing the Controller Module which I don't want you to do right now.  I appreciate you sending the captures which I assume are your attempt to establish a telnet session.

                                                                                         

                                                                                        I will contact you direct tomorrow morning as I'm work with another customer on a service outage now.

                                                                                         

                                                                                        Thanks,

                                                                                        R. Fox

                                                                                          • Re: Telnet not working?
                                                                                            cbh New Member

                                                                                            Ok. Tomorrow is fine.

                                                                                             

                                                                                            FYI, the sniffer captures show my laptop attempting to connect, but the Adtrans simply return an RST packet. There is no negotiation, simply 3 iterations of RST packets and it’s done.

                                                                                             

                                                                                            Charles Harrison

                                                                                            Sr. Telecommunications Analyst | XTO Energy

                                                                                            Desk: 817-885-1648 Cell: 817-201-2794

                                                                                            • Re: Telnet not working?
                                                                                              cbh New Member

                                                                                              Thanks for the message. I have not attempted to access the unit via the craft port. Is that a serial connection?

                                                                                               

                                                                                              Charles Harrison

                                                                                              Sr. Telecommunications Analyst | XTO Energy

                                                                                              Desk: 817-885-1648 Cell: 817-201-2794

                                                                                        • Re: Telnet not working?
                                                                                          adtn99 Employee

                                                                                          Cbh can you place an Ethernet sniffer between your laptop and the MX2800 and tell us what you see in both directions?

                                                                                           

                                                                                          R. Fox

                                                                            • Re: Telnet not working?
                                                                              jayh Hall_of_Fame

                                                                              We have several of these in the field, many with uptime of several years.  Telnet just works, I've never had an issue.

                                                                               

                                                                              If I had to guess I'd say that something is disconnecting telnet sessions uncleanly in your environment.  Either a NAT box or firewall with a short TCP timeout or a very lossy network. 

                                                                               

                                                                              I would strongly recommend putting these as well as any other network devices on a private network behind a firewall and VPN rather than depend on the hosts list on the mux itself.  As the Adtran folks here have mentioned, this is a very mature product.  There isn't a CIDR or subnet option for allowed management, and no SSH so all communication will be unencrypted. 

                                                                               

                                                                              Another option for smaller deployments is to use the craft (console) RS232 port if you have a Cisco router on-site that has an AUX port.  You can "reverse telnet" to the mux via the AUX port. 

                                                                                • Re: Telnet not working?
                                                                                  adtn99 Employee

                                                                                  I forwarded your comments to the MX2800 Engineer and he agreed with your assessment of the possible causes of the issue.  He also agreed with your proposed solutions as well.

                                                                                   

                                                                                  We appreciate your participation to the ADTRAN SUPPORT COMMUNITY!!!!!!!!!!!!!!!!!!!

                                                                                  • Re: Telnet not working?
                                                                                    jbell New Member

                                                                                    Jayh,

                                                                                     

                                                                                    In our environment, both of our MX2800's are behind more than one firewall/security system, but all connections to them are from the same internal network - never from an outside network or via a VPN.  As for a "lossy network", if we were having issues of that nature, our Network Engineers would have been fired as that would not be tolerated.  I can't begin to describe how strict they are around here about everything working perfectly and eliminating people that can't make it so.   

                                                                                     

                                                                                    With the Change Control management processes and Disaster Recovery requirements that we have, some requested tests are simply not practical for us to attempt.  I'd love to lock it down to specific IP addresses for access, but that is simply not possible given our policies and procedures.  Even if it did solve the issue, it would mean that their IP ports are not resilient enough, and are unsuitable to our use.  I already suggested the possibility, and since no other devices on the LAN are having issues, that would be their take on it.

                                                                                     

                                                                                    We have two of these exhibiting the same problem, with the following software versions...

                                                                                     

                                                                                    x    Code Version = 3.42A                Code Version = 3.42A                  x

                                                                                    x    Code Checksum = 1F5F                Code Checksum = 1F5F                  x

                                                                                    x    Boot Version = 1.00E                Boot Version = 1.00E                  x

                                                                                    x    Boot Checksum = AFEF                Boot Checksum = AFEF                  x

                                                                                     

                                                                                    and

                                                                                     

                                                                                    x    Code Version = 3.42A                Code Version = 3.42A                  x

                                                                                    x    Code Checksum = 1F5F                Code Checksum = 1F5F                  x

                                                                                    x    Boot Version = 2.20A                Boot Version = 2.20A                  x

                                                                                    x    Boot Checksum = 0820                Boot Checksum = 0820                  x


                                                                                    I also double-checked with our Network Engineers, and the IP addresses for both of these are excluded from our port scanning system and have been since it was first suggested by Adtran support some time ago.  Between all of the various devices on our network from a variety of major manufacturers, these two boxes are the only ones having this issue.  So while it seems to be understood that the MX2800 does not react well to port scans, that isn't happening to them here.  They verified that the ports they are on are not being scanned.

                                                                                     

                                                                                    I only came on board two months ago and have been tasked with finding a solution to this, or implementing an alternative hardware solution.  Fortunately the units continue to perform their primary function, so they have had a measure of patience on getting the Telnet issue resolved.  But I am being pressured to make this work.

                                                                                      • Re: Telnet not working?
                                                                                        jayh Hall_of_Fame

                                                                                        When telnet fails, does it hang and time out or immediately return "connection refused"?

                                                                                         

                                                                                        Short of a reboot, is there anything that returns telnet functionality?  For example unplugging and reconnecting the ethernet cable?

                                                                                         

                                                                                        Any errors on the connected switch interface?

                                                                                         

                                                                                        Other IP-based services also broken?  SNMP for example? 

                                                                                         

                                                                                        Unfortunately I don't have any further suggestions short of continuing to work with Adtran support or putting in something like a console server to the craft ports. 

                                                                                          • Re: Telnet not working?
                                                                                            ronnieb New Member

                                                                                            I get “could not open connection to host, on port 23: Connect failed.

                                                                                             

                                                                                            It was working when I put IPs in the security section but now has stopped working.

                                                                                             

                                                                                            I don’t believe so to answer your third question but would have to double check.

                                                                                             

                                                                                            Ron

                                                                                              • Re: Telnet not working?
                                                                                                jayh Hall_of_Fame

                                                                                                ronnieb wrote:

                                                                                                 

                                                                                                I get “could not open connection to host, on port 23: Connect failed.

                                                                                                 

                                                                                                Does this happen immediately when you issue the telnet command or does it take several seconds?

                                                                                                 

                                                                                                If immediately, it indicates that the TCP connection attempt reached the target and the device returned a FIN/ACK refusing the connection.  If after several seconds it means that the TCP connection attempt timed out, either the mux didn't get the request or its ACK didn't reach the sender.

                                                                                                 

                                                                                                One other possibility...

                                                                                                 

                                                                                                Could there be a duplicate IP address on the network of another device without the telnet port open?  When telnet fails, if you disconnect the ethernet port from the mux, can you still ping it?  If so, start hunting for another device with the same IP.

                                                                                                  • Re: Telnet not working?
                                                                                                    adtn99 Employee

                                                                                                    jayh,

                                                                                                     

                                                                                                    Your responses/suggestions indicate you're very knowledgeable about IP networks as well as the MX2800!  I'm encouraged by the fact the other users are following up on some of your suggestions! 

                                                                                                     

                                                                                                    The only thing I can add to your list of suggestions is if all else fails for the users they should open a Technical Support Ticket by calling 800-726-8663.  There is no charge for doing so and if we're at a point where we suspect the IP interface of a chassis or a controller card issue we can then discuss an RMA, which I cannot do from the Support Community platform.

                                                                                                     

                                                                                                    Appreciate your participation on our Support Community platform!!!!!!!!!!!

                                                                                                     

                                                                                                      

                                                                                                     


                                                                                                    • Re: Telnet not working?
                                                                                                      jbell New Member

                                                                                                      jayh,

                                                                                                       

                                                                                                      The rejection is immediate.  I have also looked for duplicate addresses.  Sadly, that's not the root cause here - if it were only that simple...

                                                                                                       


                                                                                                • Re: Telnet not working?
                                                                                                  adtn99 Employee

                                                                                                  jbell please elaborate on your comment regarding two MX2800 systems exhibiting the problem.  Am I to understand your company has two MX2800 system deployed?  Or your company has multiple MX2800 systems deployed and only two of them are giving you grief?

                                                                                                   

                                                                                                  The three customers I dealt with regarding IT Security program which you reference as "port scanning" was told the same thing by their respective IT departments, but when we instituted IP Security/One IP Host to tightly control Telnet access to the MX2800 the Telnet failures ceased/stopped hence my reasoning for suggesting this as a test to see what impact it would have on your MX2800s.

                                                                                                    • Re: Telnet not working?
                                                                                                      jbell New Member

                                                                                                      We have two MX2800's with both exhibiting the same issue.

                                                                                                       

                                                                                                      I have checked twice with our Network Operations folks, and they triple-checked that the IP addresses for our MX-2800's are excluded from all scanning processes.  Is it possible they are mistaken?  Yes.  However, I have had them check three times now - including going to different people each time.

                                                                                                       

                                                                                                      I'm still trying to see if I can find a way to implement your suggestion, but with our requirements I don't see it happening.  If it turns out that the root cause is how the MX2800 reacts to scanning, then our Executive Management group will consider the MX2800 unsuitable to our environment, and any future purchases will have to come from another manufacturer - or from a different product line.

                                                                                                       

                                                                                                      Has your chassis-based system had this same issue reported?

                                                                                                        • Re: Telnet not working?
                                                                                                          jayh Hall_of_Fame

                                                                                                          I just ran nmap against a few of our muxes, it didn't affect the ability to telnet at all.  We're also running 3.42A firmware.  It might be useful to try some SNMP get commands when in this state to see if the problem is all IP connectivity or just telnet. 

                                                                                                          • Re: Telnet not working?
                                                                                                            adtn99 Employee

                                                                                                            jbell,

                                                                                                             

                                                                                                            I've already stated several times it's possible the two MX2800 chassis in question might have LAN Interface issue i.e. no different than having an issue with the ethernet cord.  However we have to do some testing to prove one way or the other which will require you to open a Technical Support Request 800-726-8663.  I will also need the S/N of the MX2800 chassis in question before we can discuss an RMA as a possible option.

                                                                                                             

                                                                                                            Ideally I'd like to isolate one of the MX2800s in question from the current Management IP Network and try accessing via the LAN Interface everyday for however many days it would take to prove whether or not the MX2800 is the source of the issue or the Management IP Network.  I know such a test wouldn't be easy to pull off, but if you will open a Technical Support Request I'm sure we can work something out.

                                                                                                             

                                                                                                            I'm not sure what you mean by chassis based system?  Can you be more specific i.e. provide the P/N# or Product designation?

                                                                                                             

                                                                                                             

                                                                                                             


                                                                                                              • Re: Telnet not working?
                                                                                                                jbell New Member


                                                                                                                By chassis-based I was referrring to the 2820.  Have there been any reports of this issue on that product?

                                                                                                                  • Re: Telnet not working?
                                                                                                                    adtn99 Employee

                                                                                                                    The MX2820 & MX2810 products are Telco Central Office M13 platforms whereas the MX2800 was developed for the end user customer premise application.  Functionally these products are all M13 platforms DS3 Network facility dropping 28 DS1s.  No, there haven't been any reports on these products like you're experiencing with the MX2800.  However, I don't know what would happen if we simply substituted an MX2820 for your MX2800 utilizing the same LAN/IP Remote Management in place?

                                                                                                                     

                                                                                                                    We can discuss further via Tech Support RQST00001542420.

                                                                                                                      • Re: Telnet not working?
                                                                                                                        jbell New Member

                                                                                                                        I can report that having replaced the individual 2800's with the 2820, we had no issues with the 2820 telnet.  We used the same physical port on the cisco switch that one of the 2800's was plugged into, and the same IP address as one of the 2800's, and everything is working correctly on the 2820.

                                                                                                                         

                                                                                                                        Basically, we removed the 2800, and plugged evertyhing into the 2820.  We gave the 2820 the same IP address, gateway, etc. as the 2800 we removed, and it all works fine.

                                                                                                                         

                                                                                                                        We have since removed all of our other 2800's and are using the 2820 to handle their functions.

                                                                                                                          • Re: Telnet not working?
                                                                                                                            adtn99 Employee

                                                                                                                            Jbell,

                                                                                                                             

                                                                                                                            I'm glad to hear the MX2820's remote management via IP is working without any issues!  I have no clue as to why the MX2800 didn't behave in a like fashion on the same IP Network?  We've gotten a handful (4 to 6) customers experiencing the same issue with their MX2800's, but we've never been able to duplicate the loss of telnet access on the Controller Modules provided to us from these customers tested in our Tech Support Lab managed via our IP Network!  Initiating IP Security Provisioning within the MX2800 resolved the loss of Telnet access for two or three of the customers.  We also requested Wire Shark captures from a couple of the customers, but they never provided any that we could pass on to Engineering.

                                                                                                            • Re: Telnet not working?
                                                                                                              adtn99 Employee

                                                                                                              I recently worked with an MX2800 customer with a similar issue i.e. loosing remote access every seven days or so.  The site was a new data center with all new equipment and I informed the customer the MX2800 LAN Interface supports 10Base-T only which prompted him to check the LAN Interface of his router and discovered it was set for 100mb.  He reconfigured the router's LAN Interface to 10mb and hasn't lost remote access since making the change. Going forward we recommend configuring the IP/LAN Interface to match the MX2800's LAN Interface 10Base-T.