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Cisco 2610 12.3.5 NAT Bug?

Unanswered Question

So... I've been running many versions of IOS on many routers and never had any problems with CBAC Firewall, NAT, public IP on the outside, private range on the inside - fairly straightforward. On this particular router, I've been running software with the IP/FW/IDS PLUS IPSEC 3DES feature set from probably 12.2.8T through 12.3.3a with no problems, the configuration hasn't really changed much.

However, with my working configuration on 12.3.3a, I tried out the new Nov-17 build of 12.3.5 and mysteriously none of my outside NAT translations go through to internal machines. I verified that there is no access list denying the packets on the outside interface - specific ACL permits with log showed this, and the NAT translation was being created according to debug as well... I spent 30 minutes trying to figure out what was going on.. I reloaded the old 12.3.3a IOS with exactly the same configuration and it works fine now.

Is this a bug? I did find this very strange.


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Georg Pauwen Sat, 11/22/2003 - 01:54
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I checked the bug toolkit, not really much there, except for a possible problem with multiple inside IPSec clients and CEF enabled. Recommended workaround: disable CEF. Not sure if this applies to you.



Tsasbrink Fri, 01/02/2004 - 05:41
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I too experiance these strange behaviors. i used 12.3.5. on a 3620 but allso downgraded again becuse it misteriqously stoped working without any notification within 5mins of booting.


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