Hi

I am having some unusual issues with dns on one of my servers.

If i ping the domain name only 1 packet is returned and the lest are lost, pinging the ip numbers is fine though.

Also if i try connecting to other servers from that server using ssh it takes ages to ask for the password. I have checked the resolv.conf file and its fine.

Any help would be much appreciated.

Hi,


check /etc/hosts
check route table!!!
if you use ipchains - check it

it would be also useful to test your dns via nslookup or dig

Thats the /etc/hosts file


65.193.180.130 www.server3indallas.com www
127.0.0.1 www localhost.localdomain localhost


I presume the route table is something my isp will have to check, i tried disbaling iptables, that made no difference.

Hi

Don't be offended, but if you think that "the route table is something my isp will have to check" - you better need to ask admin help.

try /sbin/route and look on

But! Actually you did not describe your problem completely
1. It's very strange that ping work different with name and ip.
Ping resolve ip by name and then use it, so ...
2. What dns do you ping? Your own or someone
3. SSH is not a symptom

Regards

I agree, this is very weird. Ping works on IP level, it only does DNS lookups on start up to find the IP address. I guess this is a bug in your ping binary, try upgrading your ping (in redhat, try upgrading iputils package) to a later version, and see if the problem persists.

erapid, i dont try to know everything, just enough to get me by with the day to day running of the servers.

I have already asked my server provider for assistance, but havent got any yet.

I dont see why the thing with ssh isnt a sympton.

The main problem with this is that its stopping the cpanel transfer script from working and i need to move some sites.

I figured out both of the problems.

Something's wrong with the ping binary that comes with Red Hat 7.2 because I can reproduce your problem on every Red Hat 7.2 box. (Damn Red Hat...)

As for the SSH problem, that's a totally unrelated issue. Other servers are trying to resolve your IP address, but times out, that's why it takes ages to ask for the password.

$ host 65.193.180.130
(sits there for about 12 seconds...)
;; connection timed out; no servers could be reached

That's a reverse DNS misconfiguration that your provider will have to fix.

I hope that helps. :)

If you do a "ping -n" that will tell it not to lookup the hostname of the IP address you're pinging, should eliminate the problems you're having with ping.

Originally posted by billyjoe
If you do a "ping -n" that will tell it not to lookup the hostname of the IP address you're pinging, should eliminate the problems you're having with ping.

So it tries to resolve the IP address when you specify a host name? :eek: That's very unnecessary. :rolleyes: No wonder. I guess the two problems are related after all.