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CSS DNS host, client TTL question

We have two CSS devices set up as DNS host for our failover scenario.

This works well, but I had a question about the TTL in the config for the DNS a-record.

Currently our records are set as follows:

dns-record a 50 single kal-icmp 254 sticky-disabled weightedrr 0

My questions are:

What is the TTL setting as far as the client doing?

Does the client, when getting the name resolved via the CSS, know that the ttl is 50 seconds and will not try again to hit the CSS until after the 50 seconds is up?


Re: CSS DNS host, client TTL question

When you add the DNS name to the content rule, you may also enter an optional Time to Live (TTL) value in seconds. This value specifies how long the DNS client remembers the IP address response to the query. Enter a value from 0 to 255. The default is 0.

Note You must configure the TTL when you add the DNS name to the content rule. To add a TTL to an existing rule, use the remove dns command to remove the dns name. Then use the add dns command to reconfigure the DNS name with a TTL value.

For example:

(config-owner-content[])# add dns 36

Use the (config) dns-server command to configure the DNS server functionality on a CSS.