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Anonymous
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FIREWALL: EVENT MESSAGE

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Why would this message show up after every 2 secs on TA908e

2012.02.29 17:09:58 FIREWALL id=firewall time="2012-02-29 17:09:58" fw=LES_TA908e pri=1 proto=udp src=64.105.124.154 dst=69.3.137.94 msg="IpReasmbly time out" agent=AdFirewall

is there a way to suppress this?

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Anonymous
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Re: Why would this message show up after every 2 secs

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Thank you for posting this question.  Firewall threat messages could possibly be attacks, but not necessarily as they could also be caused by misconfigurations or peculiarities in the network. In AOS, threats have been categorized and been assigned a weight based on their possible severity. Threats with a higher severity have the potential to be more compromising to hosts behind the firewall than threats with a lower severity.

The threat you have displayed above is a minor threat, and virtually can be ignored.  You can disable this message from appearing on the CLI, per session, by issuing the no events command.  For future reference I have detailed this particular threat below, as described in our IPv4 Firewall Protection in AOS guide:

Short Definition: Reassembly timeout

Description: Indicates that the fragments necessary to complete reassembly

have not arrived in a timely manner. An attacker could have attempted to

consume all of the resources in the reassembly engine of a server or other

network device.

Action: The reassembly engine drops the offending fragments and frees the

resource.

I hope this makes sense, but please do not hesitate to reply to this discussion with further information or questions.  I will be happy to assist you in any way I can.

Levi

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Anonymous
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Re: Why would this message show up after every 2 secs

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Thank you for posting this question.  Firewall threat messages could possibly be attacks, but not necessarily as they could also be caused by misconfigurations or peculiarities in the network. In AOS, threats have been categorized and been assigned a weight based on their possible severity. Threats with a higher severity have the potential to be more compromising to hosts behind the firewall than threats with a lower severity.

The threat you have displayed above is a minor threat, and virtually can be ignored.  You can disable this message from appearing on the CLI, per session, by issuing the no events command.  For future reference I have detailed this particular threat below, as described in our IPv4 Firewall Protection in AOS guide:

Short Definition: Reassembly timeout

Description: Indicates that the fragments necessary to complete reassembly

have not arrived in a timely manner. An attacker could have attempted to

consume all of the resources in the reassembly engine of a server or other

network device.

Action: The reassembly engine drops the offending fragments and frees the

resource.

I hope this makes sense, but please do not hesitate to reply to this discussion with further information or questions.  I will be happy to assist you in any way I can.

Levi

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Anonymous
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Re: Why would this message show up after every 2 secs

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I marked this question as "assumed answered," but please feel free to reply if you have further questions on this topic.

Levi

Re: Why would this message show up after every 2 secs

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2 questions, 1) what is the timeout value? and 2) is there a way to increase this value? or alternatively 2b) is there a way to disable this check?

Anonymous
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Re: Why would this message show up after every 2 secs

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I stumbled in here looking for something else. Then did a quick detour out of curiosity.

Sorry I don't know the answers to your specific questions, (I'm fairly certain Support will say the timer isn't programmable). I don't think you'd want to disable a firewall check and resulting resource clean up..

You may long since have discovered an issue, but if the messages were consistently related to the source 64.105.124.154 as shown in your example, then my quick internet search shows people were using that as a DNS server. (Perhaps at Covad).

So perhaps it was slow completing DNS responses and causing fragmented responses to time out. (people were complaining about it's performance).

Changing DNS servers would have been a good test at that time. there are some good public DNS servers out there. (I've used 4.2.2.1 in the past)

...moving on with my original search

Cheers - Glen