Slow response from DHCP server (Redhat Enterprice Linux 5 with ISC DHCPd)

I experience my DHCP server uses quite long time to respons to my DHCP request. Sometimes up to 20-30 seconds. I've been reading about DNS/Reverse, so I included "ddns-updates off;" in the dhcp zone file. This did not help.

I'm experiencing the same delay connecting with SSH. Dont know if this is related, but it seems logic to me it is.

Any ideas?
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Your firewall ? is it large? sometimes if it is, the computer/server have problems looking up the rules and takes time before it comes down to the rule  regarding SSH/dhcp.

It might be the problem after experience.

Regards Aamodt
erikleirdalAuthor Commented:
There is no firewall. I've also removed the ACL for the moment to be truly sure everything is open. I really suspect somthing at the server, but I'm not able to pinpoint what it is.. :)
same delay connecting with SSH. :
There could be a reason.., ssh hang for long if it does not get a dns server address.

Where is the dns server ???

is dhcp sending dns address properly ??
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erikleirdalAuthor Commented:
this is a local network only with private IP's. I dont really care about DNS so I prefer to "turn it off"...

or do I need to build the DNS host files to get around this issue?
I actually dont use linux base dhcp server that much......

but about your SSH delay ... i know this is because of dns problem(if this the one i am thinking)

you can try to add this config in sshd daemon

UseDNS no

then restart ssdh daemon  

try to connect via ssh  .. see if its solved that issue...

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try to configure  dns host on the same dhcp server , it might fix the issue.. it could be the delay for some sort of dns query .....

erikleirdalAuthor Commented:
I'm currently installing DNS deamon, so I will see how it goes.. :) tnx so far! :)
but your UseDNS no  in sshd_config

did not make any differences ???
erikleirdalAuthor Commented:
yes it helped :-) tnx alot.. that points me to DNS also for DHCP ;-)
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