Slave DNS cache time

I have my ISPConfig server setup as a slave DNS from my primary windows dns box. Anyways.. My primary DNS went down last night, and I noticed that this morning the ISPConfig was also down. Just to be sure, was this because the TTL was too short?

Thanks

 

What exactly went down? A single service (DNS), or the whole server, or was just the name resolution not working anymore?

 

The whole system went unresponsive until i could reboot it the next day.

 

Did you check your logs? I doubt this has anything to do with the TTL. Maybe your system was hammered with DNS queries because the primary DNS was down.