topic Re: DNS server reply timeout/retry in Operating System - HP-UX

DNS server reply timeout/retry

viseth — Wed, 02 Nov 2005 11:40:36 GMT

Hi everyone,

Does someone know how to change the DNS reply timeout and the DNS number of retries? I have a DNS client that does not wait long enough for a answer from a given DNS server and does not attempt to retry it query to the given DNS server, so that it send that query to another DNS server.

Many thanks for your feedback!

regards,

\Viseth

Re: DNS server reply timeout/retry

A. Clay Stephenson — Wed, 02 Nov 2005 11:44:48 GMT

Do a man 4 resolver; it will explain how to do this.

Re: DNS server reply timeout/retry

A. Clay Stephenson — Wed, 02 Nov 2005 11:47:49 GMT

I should also add that in addition to changes in /etc/resolv.conf you can also set and export these environment variables:

RES_RETRANS=3000 # milliseconds
RES_RETRY=5

These are explained in the man 3n resolver man pages.

Re: DNS server reply timeout/retry

viseth — Wed, 02 Nov 2005 12:09:12 GMT

But I do not find thoses parameters when I do a man resolver... Besides, do those parameters need to be set directly in the /etc/resolv.conf??

many thanks
regards,

\Viseth

Re: DNS server reply timeout/retry

viseth — Wed, 02 Nov 2005 12:16:37 GMT

Hi A. Clay Stephenson,

Thanks for the answer, I've found on internet the man 3n resolver pages. On my unix (solaris 2.8) the man does not states thoses parameters... maybe the version of the resolver is not the same, isn't it?

Regards,

\Viseth

Re: DNS server reply timeout/retry

A. Clay Stephenson — Wed, 02 Nov 2005 12:16:53 GMT

There is a difference between "man resolver" and "man 4 resolver" or "man 3n resolver".

In any case, you can set the environment variables as I indicated or you can add these entries to /etc/resolv.conf.

retry 6
retrans 6000

Note: The values in /etc/resolv.conf have higher precedence than the corresponding environment variable settings.

Re: DNS server reply timeout/retry

viseth — Wed, 02 Nov 2005 12:27:10 GMT

Hi A. Clay Stephenson,

Thanks for the reply! Do you know if it is possible to do the same with microsoft DNS client?

Many thanks,

Regards,

\Viseth

Re: DNS server reply timeout/retry

Florian Heigl (new acc) — Wed, 02 Nov 2005 14:11:41 GMT

One addition: These parameters are supported by all HP-UX versions >=11.11, for 11.00 You need two specific patches.
They're no hassle, but one requires a reboot.

In any case it's worth the effort.

Re: DNS server reply timeout/retry

viseth — Thu, 03 Nov 2005 03:45:05 GMT

Is this parameters supported as well for other plate-forms solaris, aix...
many thx

\Viseth

Re: DNS server reply timeout/retry

Brian Hackley — Thu, 03 Nov 2005 07:31:22 GMT

Viseth,

Solaris does support the retry/retrans also. At 2.6, the syntax there is retry:1 retrans:1000.

My typical recommended values for typical customer environment is 1 retry after 1 second / 1000msec. Your milage will vary.

For those of you missing the info from the HP-UX resolver() man page it is because it was missing until the libc man page patch is installed. 11.0 patch PHCO_24904 (latest is PHCO_31919) 11.11 patch PHCO_24915 (latest is PHCO_29829).
No patch needed for 11.23, it's man page also has the info.

HTH,

Brian Hackley