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New Member

FragGuard and Virtual Re-assembly

Hi folk,

Any idea what the subject above on pix 5.1 does ?

Apparently I'm receiving a huge number of error messages pertaining to it:

fh_insertb: too many fragments(12) in set

If it's a security attack, how can i stop it ?


Re: FragGuard and Virtual Re-assembly

Which exact version of PIX are you running (5.1(x))? There was a bug in early 5.1 code you might be running into. If you’re on 5.1(4) and you are still getting a lot of frags, the PIX is doing it’s job by blocking them. If you need to know about them, put a sniffer/analyzer on that wire and look at the fragments to learn what’s going on.

New Member

Re: FragGuard and Virtual Re-assembly


I am getting this same error, but only when I transmit packet from a UNIX enviornment to an NY enviorment. I am running 5.1(4). Any help would be appreciated.

New Member

Re: FragGuard and Virtual Re-assembly

Some Unix (Linux e.g.) transmit IP fragments in revers order. Fragmented Linux packets will not pass through the Pix with sysopt security fragguard enabled.

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