Thursday, October 14, 2004

Customer Questions:

- If you have to set the expire time for DNS to 300 sec instead of whatever the standard is (ours is 604800), doesn't this mean we are going to generate even more network traffic than we already have?

1) Yes, you are correct that additional DNS queries will be made, however the average DNS request is tiny (less than .5 Kbytes), and this is smaller then just about any other type of traffic. Other redundancy solutions, like BGP or OSPF, use much larger packets than our dynamic DNS solution.

- What happens when requests are initially sent to ns2 first instead of ns1 while the T1 line hasn't hit the threshold? Will the requests be rerouted back to ns1? If so, won't this add extra time to the overall process?

2) There is no additional processing time required based on the WAN link the request came in on. Both ns1 and ns2 on the Edge device respond dynamically. They are not tied to either WAN interface. So if a request came in on WAN1, it could provide WAN2's IP information if that is how the vector routing engine has determined its response.