Slow resolution

The problem I am having with my Redhat DNS is slow resolution. All devices can resolve addresses fine, but it takes 45 - 60 secs for a request. I found out, however, that if I append the domain that the resolution is practically instantaneous. For example:

"nslookup management" is slow

"nslookup management.domain" is fast

All resolution is local, so I don't want to resolve to the Internet or any other domains. I don't have any parent or slave zones either.

What does your resolv.conf look like.

This is the 'resolv.conf' on my nameserver. Resolving on this device takes less time, about 10 secs when using just the host name. However, it is still faster (instantaneous) if I use the fully-qualified domain.

-- resolv.conf --
domain lab.reno
nameserver 127.0.0.1
nameserver 172.24.200.200
options timeout:2
----------------

Thanks for your help

Try renaming the resolv.conf so that it isn't used. Then try nslookup again. Tell me if it's fast this time.

the dns was unable to resolve when I renamed resolv.conf:

'management: Host name lookup failure'

Dunno then. I'm thinking this is a system configuration problem. Certainly hostname's aren't being sent to the DNS server. The DNS server only supports fully qualified domains. nslookup has to translate your hostname into a fully qualified domain before it can send the query. To do this it uses resolv.conf. I don't know much about resolv.conf so if there's a problem with it, I don't know what it is.

All I can suggest is to not use hostname ever. Always specify fully qualified domains in all commands and configurations.

Unfortuantely, we use the hostnames to telnet into network devices. The dns is a convenience so that we don't have to type in/remember the entire IP. In other words, brevity is important.

Is there any way to append a specific domain to all outgoing dns requests? I only have one domain for all hosts. Perhaps a name-caching server?

Well tell ya what, let's try something else. type this into the commandline and paste for me what you get:

dig -x 127.0.0.1
dig -x 172.24.200.200

Here is the output:
-------------------
First Command
-------------------
[root@ns1 etc]# dig -x 127.0.0.1

; <<>> DiG 9.2.1 <<>> -x 127.0.0.1
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 5439
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; QUESTION SECTION:
;1.0.0.127.in-addr.arpa. IN PTR

;; ANSWER SECTION:
1.0.0.127.in-addr.arpa. 86400 IN PTR localhost.

;; AUTHORITY SECTION:
0.0.127.in-addr.arpa. 86400 IN NS ns1.lab.reno.

;; ADDITIONAL SECTION:
ns1.lab.reno. 259200 IN A 172.24.200.200

;; Query time: 2 msec
;; SERVER: 172.24.200.200#53(172.24.200.200)
;; WHEN: Fri Jul 9 15:12:34 2004
;; MSG SIZE rcvd: 107

---------------------------
Second Command
---------------------------
[root@ns1 etc]# dig -x 172.24.200.200

; <<>> DiG 9.2.1 <<>> -x 172.24.200.200
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 56672
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;200.200.24.172.in-addr.arpa. IN PTR

;; Query time: 2 msec
;; SERVER: 172.24.200.200#53(172.24.200.200)
;; WHEN: Fri Jul 9 15:12:53 2004
;; MSG SIZE rcvd: 45

I see the IP address 172.24.200.200 fails to resolve to a domain. Fix that and see if nslookup continues to be slow. My suggestion is that you point the IP at lab.reno just like you have set in resolv.conf.