NS issues

[Andrew Bacchi]

In my case, the application client caches the server address internally. 
  Unless I flush this client cache it keeps trying to connect to the old 
IP address.  You may have a similar situation.

One possible solution is to reboot the standby machine with the IP 
address and hostname of the failed machine.  It's less work to do that 
than change DNS records.

Flynn, Neill wrote:
> Hi all,
> 
> I'm a Solaris admin who has a few RH boxes to look after. We use NIS and 
> DNS for name resolution. The NIS host file gets updated by hand and the 
> DNS server uses this information to create it's named DB's. All clients 
> are setup to use "files, NIS, DNS" in their nsswitch.conf.
> 
> We have 3 boxes running propriety software (all on the same subnet), two 
> run in production and one is a backup. I created an alias for each of 
> the primary machines which is now used for accessing the services on 
> that box. "In the unlikely event of a failure", the plan is to switch 
> the alias from the faulty primary machine to the backup machine and 
> restart all services.
> 
> During testing, I changed the alias and updated DNS (I had a wee problem 
> with the TTL for the DNS zone - as these machines actually use a 
> secondary DNS server - this was overcome and all seemed fine). When the 
> application support lads went to startup the application, it was still 
> trying the old IP address of the aliased hostname.
> 
> I checked everything I could think of (mainly from a Solaris 
> perspective)…./etc/nsswitch.conf, /etc/resolv.conf, ypmatch, nslookup, 
> arp, nscd (which isn't running)……anyway I found nothing obvious. Can 
> anyone suggest anything else that I should look at?
> 
> Thanks in advance for any help,
> Neill
> 
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		-Seneca

Andrew Bacchi
Systems Programmer
Rensselaer Polytechnic Institute
phone: 518.276.6415  fax: 518.276.2809

http://www.rpi.edu/~bacchi/