I am working with a PIX-506 (v5.2.3) configured to receive a DHCP address from the ISP that will be assigned to the outside interface. It is also configured for PAT and DHCP Server for the inside users. The PIX is fully functional for a period of time. This period of time varies from 1 day to 1-2 weeks. After this period of time, the PIX will reset it's outside interface to the loopback address 127.0.0.1.
At one time I opened a case with TAC and sent them a "show-tech" output, but we didn't have any success determining a cause. I originally had this problem with v5.3.1 and I downgraded to 5.2.3 on the advise of TAC. I see that v5.2.5 is now available. I may try that to see if I have any different results.
One of the more frustrating things about this is that when doing "show and debug" commands on the PIX, there is no obvious way to see that it has been fixed until the problem crops up again.
I have a theory that this may be occuring when the DHCP lease from the ISP expires. If this is the case, I am uncertain why the problem reoccures at different intervals. One would think it would happen on a regular basis at every lease renewal.
I am hoping that someone else has seen that same issue and can point me in the right direction. Any assistance would be greatly appreciated!
I think you are going to have to capture sniffer traces during the event to determine whats coming from the ISPs DHCP server. With that you can go to Cisco to determine if its a bug in the code or not.
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...