ACE DNS Balancing and show serverfarm

[omarmontes]

Hi guys..

We are implementing a couple of ACEs for DNS loadbalancing. We are seeing some weird stuff:

1.- When using the feature udp-fast-age, (so we do balance even if using the same IP for the DNS queries), the "show serverfarm X" shows a lot of failures.

2.- If we remove the feature, the are a lot of less failures (1500 of 180000), we get no loadbalance (expected, since the queries are from 1 IP address and source port), BUT, if we do the queries pointing to the real server, we get a better connection ratio than using the VIP. (only like 15 failures). Is this expected? seems to me like a lot of failures if using the VIPs.

3.- the "show serverfarm" almos never shows connections, is this because the udp nature of DNS? Does it works better for TCP connections?

If you need to see our config, pls tell me.

thanks in advance!

omar m

[jasmina27s]

Hello,

I'm not sure why you are seing this behaviour...

We use ACE module for DNS load balancing and it seems OK (we do not use "udp-fast-age" or any other specific feature...):

switch/DNS#  sh serverfarm DNS
serverfarm     : DNS, type: HOST
total rservers : 3
---------------------------------
                                                ----------connections-----------
       real                  weight state        current    total      failures
   ---+---------------------+------+------------+----------+----------+---------
   rserver: DNS_1
       xxx.xxx.xxx.21:0     8      OPERATIONAL  12454      3735270717 0
   rserver: DNS_3
       xxx.xxx.xxx.25:0     8      OPERATIONAL  12452      3735270973 1
   rserver: DNS_5
       xxx.xxx.xxx.29:0     8      OPERATIONAL  12476      3735268988 1

Maybe you should post your config and show command output?

Best regards,

Jasmina