North American Network Operators Group|
Date Prev | Date Next |
Date Index |
Thread Index |
Author Index |
Re: SYN spoofing and Ciscos crashing
- From: jlewis
- Date: Wed Jul 28 16:43:23 1999
On Wed, 28 Jul 1999, bryan s. blank wrote:
> % ip verify unicast reverse-path
> % and according to Paul Ferguson (co-author of RFC 2267) it's in use by
> % many ISPs. Apparently this is very-low overhead. Paul has also indicated
> % the use of extended access lists on Cisco routers is very low overhead,
> % especially on routers using distributed express forwarding.
> while i hate to question mr. ferguson, it's my understanding
> that many isps have found this feature to be unusable due to
> network design.
I just took out a 7206 by applying ip verify unicast reverse-path to a T3
link on a PA2T3 and attempting to spoof packets from the POP on the other
end of that T3.
The 7206 is running c7200-inu-mz.111-25.CC. Fortunately, it rebooted
after it crashed.
System restarted by bus error at PC 0x605F88CC, address 0x10024 at
20:29:49 UTC Wed Jul 28 1999
This router had been up over 8 weeks without a crash (ever since Cisco
replaced the previous 7206 in this POP that was either posessed or a
lemon). The memory is Cisco memory. All the parts came directly from
Is this known to be unstable in 111-25.CC? Is it known to be stable in
some other release that supports the PAT3, PA2T3, and PA-MCT3?
----don't waste your cpu, crack rc5...www.distributed.net team enzo---
Jon Lewis *firstname.lastname@example.org*| Spammers will be winnuked or
System Administrator | nestea'd...whatever it takes
Atlantic Net | to get the job done.
_________http://www.lewis.org/~jlewis/pgp for PGP public key__________