Bug: NAM does not rotate between multiple nameservers?

[seidelt]

Our NAM is configured to use three nameservers:

root@nam.our.domain# show ip
IP address:             10.69.225.11
Subnet mask:            255.255.255.0
IP Broadcast:           10.69.225.255
DNS Name:               nam.our.domain
Default Gateway:        10.69.225.1
Nameserver(s):          10.69.63.10     10.69.63.11     10.69.63.12    
HTTP server:            Disabled
HTTP secure server:     Enabled
HTTP port:              80
HTTP secure port:       443
TACACS+ configured:     No
Telnet:                 Disabled
SSH:                    Enabled

As I see in the dns request log of the nameservers, only 10.69.63.10 receives the dns requests. Checking the tech-support shows that /etc/resolv.conf does not contain the rotate option. Looks like a bug for me.

NAM image is:

NAM application image version: 5.0(1) RELEASE SOFTWARE [fc4]
PID: NAM2220

TIA for your help,

Thomas

[Nael Mohammad]

Having the rotate option in the /etc/resolv.conf file simply states to do load balancing in case the first server is busy. If the first server is healthy, it will never attempt to load balance to the second nameserver with "rotate".  With the options and timeout value present, it will try the first name server for two seconds and 1 attempt. If it fails, it will go to the next nameserver.

/etc/resolv.conf

options timeout:2 attempts:1<--- Default values

Not really a bug but can be a feature enhancement to include in future releases for DNS load balancing.

-nael

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[seidelt]

Nael,

Due to the monitoring of our dmz we see a lot of dns reverse lookups in our nameserver logs, so load balancing between multiple nameservers would be a nice speed improvement. Additional, I cannot limit dns lookups to particular subnets so there is no alternative to reduce the dns traffic.

So it would be very helpful to implement the following two feature requests in future nam releases:

* option to setup dns load balancing

* option to limit dns lookups to subnets or sites

Thanks,

-- Thomas

[Nael Mohammad · Accepted solution]

Thanks for the update, I will relay the information to Product Management team for NAM.

-nael