DNS Lookup works but how long does it remember

[dklloyd]

I wonder if anyone can help me on this....
I set-up DNS on the AIX to lookup the IP addresses on an NT DNS server with no problems and things were running fine.
Sods law says that a couple of days after the system went LIVE the DNS Server crashes, (I have taken advice from DNS issues on this site so I put the DNS server after the local lookup). However as helpfull as the network guys are here (not) they say that the UNIX box probably had something to do with the DNS server crashing and nothing to do with their box!
So I just need to arm myself for these happy chappies what DNS lookup on the UNIX box impacts on the DNS Server. We use a DHCP address system as users move between two building with there laptops at least twice a day, each being on a seperate scope of IP addresses.
The Oracle application works on a 3 tier system.
a) Does the AIX hold the IP resolution address for long after the 1st lookup or does it check with the DNS server every time an SQL statment/program is fired at it?
b) Could PCs changing their IP addresses create problems for DNS lookup.
c) Any other cautions we should take?

Look forward to hearing from you!!

 

[dklloyd]

Further to this problem I have found that indeed the IP addresses resolved using DNS are being held by the system. So if I change my IP address and ping my machine name, the system returns my old IP address, not knowing my new!!
So my line of attack must be... how do I get my machine to refresh the IP addresses to machine (host) names?

Cheers all

 

[sendhilk]

Which IP address does ur DNS server hold for ur host? the new one or the old one??

 

[dklloyd]

Hi Sendhilk
THe NT DNS Server holds the new IP address. The AIX still holds the old IP address until such time as it gets flushed out. What I need is to force it to be flushed out so that the AIX goes back to the NT DNS server for the machine name to IP address resolution, thereby getting the new address.

Thanks for responding.

 

[MikeLacey]

dk

Is the AiX box running a caching-only name server? You could restart that if it is. Mike
michael.j.lacey@ntlworld.com
Email welcome if you're in a hurry or something -- but post in tek-tips as well please, and I will post my reply here as well.

 

[dklloyd]

Thanks MikeLacey
I'm not sure is the answer to that... The resolve.conf has the DNS NameServer address of the NT DNS server and the Domain Name. The netsvc.conf contains hosts=local,bind4 .
As users move constantly between the two building (allowing 15 minutes between logins) I need the cache to hold addresses for no more than say 10 minutes.
If your suggestion can do this, what exactly is the command or procedure?

Many thanks for returning my query.