Name resolution is only working from server side. Clients cannot resolve host names.
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I think we are quite near to the problem.
If am right, you would be able to ping the nameserver ip i.e. 10.0.1.100 from the server machine i.e 10.0.1.101 but not from the client machine i.e. 10.0.1.102 as problem is only with DNS resolution
So let's say you have client 1 (C1), client 2 (C2) and a nameserver (D1).
What am suspecting is C1 is able to reach D1 while C2 can't ping D1. Please correct me if am wrong.
For that you can try adding default route on C2 to reach D1
e.g. route add default gw <ip/of/your/default/gateway>
Also, I hope that you have added the resolv.conf for client 2 odd2 as well similar to client1 odd1.
Only problem I see here is Client2 not able to reach 10.0.1.100. Could be 2 reasons:
1) Resolv.conf not configured on Client2
2) Resolv.conf configured but not able to ping nameserver (for that I suggested adding default route to your gateway), because as you said things work from Client 1, but not from Client2
Did you try using ethereal/wireshark for the question/answer section of DNS query sent from clients?
Or instead you can try:
dig A odd1.simtafco.com
or, nslookup -q=A odd1.simtafco.com
This way you would be able to verify whether the request is going to D1 or not and if going, what's the answer section?
Also, you can try comparing the output of same command from server from where resolution is working as you stated.
This time I did not install the bind-chroot package and used the standard bind. However, I hit exactly the same issue. [can ping ip addresses in all directions but hostname ping only works from server]. So I checked the udp/tcp port 53 but did not find them in netstat -an. I issued the following commands as found in google and did /etc/init.d/iptables restart but no joy. So looks like this might be the issue why my clients cannot reach the dns server. Any ideas on how to open udp and tcp port 53 please (CentOS 5)?
iptables -A INPUT -p tcp -m tcp --sport 53 --dport 1024:65535 -m state --state ESTABLISHED -j ACCEPT
iptables -A INPUT -p udp -m udp --sport 53 --dport 1024:65535 -m state --state ESTABLISHED -j ACCEPT
iptables -A OUTPUT -p tcp -m tcp --sport 1024:65535 --dport 53 -m state --state NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -p udp -m udp --sport 1024:65535 --dport 53 -m state --state NEW,ESTABLISHED -j ACCEPT
[RESOLVED] Name resolution is only working from server side. Clients cannot resolve host names.
I have resolved the issue as far as DNS is concerned. I turned off the iptables by running command "service iptables stop" ... and there it was .. all clients started pinging the hostname of DNS Server. So looks like there is some issue with iptables configuration. Unfortunately I am not very good at iptables so will research more into that and will start a new thread if required. Thanks all for your ideas and contributions.