ACS 5.4 IP name-server

[tomyip]

In ACS 5.4, the CLI command ip name-server, you can specify up to 3 IP address for DNS. It's my understanding the first IP address is the first choice, the 2nd IP is the 2nd choice, etc. I had an issue where connectivity to the first IP address of the name server was lost, then ACS went to the 2nd IP address for DNS as it should. However, when connectivity to the first name server was restored, ACS was still pointing to the 2nd name server IP address. Shouldn't ACS automatically go back to the first?

[nspasov]

Good question! I am guessing there isn't a mechanism to check the availability of the first DNS/Name server. Here is an abstract from the config guide:

Guidelines

The first name server added with the ip name-server command will occupy the first position and the system will first use that server in resolving the IP addresses.

You can add name servers to the system one at a time or all at once, until you reach the maximum (3). If you already configured the system with three name servers, you must remove at least one server to add additional name servers.

To place a name server in the first position so that the subsystem uses it first, you must remove all name servers with the no form of this command before you proceed.

It sounds silly but you will probably have to remove those servers and re-add them to get ACS to use the top server again. Or reboot the system :/

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