topic dns lookup problem(hp ux 11i) in Operating System - HP-UX

dns lookup problem(hp ux 11i)

Senthil Kumar .A_1 — Fri, 14 Nov 2003 09:04:25 GMT

hello admins,
i faced a problem while i was configuring internet on my server.when i specified my dns server ip address in the dns/bind section of my SAM utility, it was found that the server on the next boot took almost an eternity to completly boot.Infact some of the daemons like nis client failed while booting.the cde login screen took another epoch to appear.
finally i realised it was the problem with wrong order for host name lookup in nsswitch.by default it was dns,nis,/etc/hosts in the mentioned order.So ,i placed /etc/hosts as the first lookup for hostname assuming it would solve the problem.
Well it solved only half my problem ,that is it solved my slow booting problem,But,the very purpose of DNS entry was lost....I mean i couldn't browse.I tried pinging www.altavista.com from command prompt to no vail.it simply says unknown host...
is there any solution to this...

senthil

Re: dns lookup problem(hp ux 11i)

Mark Grant — Fri, 14 Nov 2003 09:10:08 GMT

/etc/hosts is the best one to have first in /etc/nsswitch.conf in my opinion but you need to make sure it is as small as possible and doesn't conflict with your nis entries. Check that the DNS server you are using is actually the right one for you. Also, make sure nsswitch.conf looks a bit like this

hosts: files [NOTFOUND=continue] nis [ NOTFOUND=continue ] dns

Re: dns lookup problem(hp ux 11i)

Kevin Wright — Fri, 14 Nov 2003 10:12:00 GMT

ensure your dns server is in /etc/resolv.conf, and in /etc/nsswitch.conf have this

hosts files [Notfound=continue] dns

Re: dns lookup problem(hp ux 11i)

Ratzie — Sat, 15 Nov 2003 18:23:07 GMT

Also shutdown the nfs client and sever in the /etc/rc.config.d/nfsconf file.

Where it states =1 change to 0
NFS_CLIENT=0
NFS_SERVER=0

This way it does not start to look for nfs

Speeds it up.

Re: dns lookup problem(hp ux 11i)

Marcel Burggraeve — Sun, 16 Nov 2003 15:49:43 GMT

Hi Senthil,

maybe you need to configure a gateway as well ?
You can do this in /etc/rc.config.d/netconf

Re: dns lookup problem(hp ux 11i)

Bill Hassell — Sun, 16 Nov 2003 23:03:56 GMT

nslookup tells you where the problemios located. You'll see messages like: looking up FILES, and Trying DNS. This is the request method for each step in nslookup. If FILES does not return anything, you'll see the next test rather than a result.Based on your symptoms, your DNS server(s) listed in /etc/resolv.conf do not work. You can prove this with:

nslookup www.hp.com firstDNSserver
nslookup www.hp.com secondDNSserver
nslookup www.hp.com thirdDNSserver

Each DNS server has a default timeout of about 20 seconds if it fails to respond. The reason bootup was so slow with DNS first is that EVERY IP_addr lookup required 20, 40 or 60 seconds to complete. By reversing the order, your local machine name is immediately resolved but your DNS servers are still dead because an attempt to query them for altavista just times out. Your DNS server administrator may have locked your local machine from using the servers.