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New Member

CE and DNS Service

I am using a CE-560 with ACNS 5.0.1 software. I have configured the DNS caching option with the following commands:

dns listen a.b.c.d port 53 hostname dnscache

dns pin both dnscache a.b.c.d

dns serial-lookup

dns max-cache-memory 10

dns enable

The problem is that after a certain amount of time the server would crash or stop answering DNS requests. One time it completely stopped answering and another time just for certain sites. I then relaized that a.b.c.d already had a DNS name and that the dns pin command may be conflicting. I changed the config to:

dns listen a.b.c.d port 53 hostname

dns serial-lookup

dns max-cache-memory 512

dns enable

So far so good, but I reconfigured it only 10 minutes ago. I deployed the DNS server this morning and by lunch it had crashed twice. I do not know what the problem is, but I have 3 ideas.

1. The DNS name conflicted with the dns pin command and confused the box.

2. The DNS cache was too small, I since raised it to the maximum.

3. The DNS service provided by Cisco is not stable.

I am leaning towards number 1. I think that the cache would just delete old entries as it approaches it maximum size and I do not believe that Cisco would deploy an unstable product.

Does anyone have any ideas?


New Member

Re: CE and DNS Service


Can you please open a TAC case for this problem. There is a know issue with the DNS cache on the CE's. The problem will be fixed in 5.0.3 release of the code which will be in May. If you require a fix earlier, then the TAC will be able to help out.

The bug ID is CSCea37278



New Member

Re: CE and DNS Service

hyaving similar problems turning on dns cache crashed my 3700 routers.

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