Visit Our UNIX and Linux User Community


ping by hostname not working


 
Thread Tools Search this Thread
Top Forums UNIX for Advanced & Expert Users ping by hostname not working
# 1  
Old 11-24-2011
ping by hostname not working

anyone ever seen this problem:

I can ping the server by IP address but I can't by hostname.

nslookup is working and dns query is ok.

Code:
[root@puppetmaster network-scripts]# nslookup mwxnsb24
Server:          10.11.49.206
Address:        10.11.49.206#53
 
Name:   mwxnsb24
Address:  10.10.58.175
    
[root@puppetmaster network-scripts]# ping 10.10.58.175
PING  10.10.58.175 (10.10.58.175) 56(84) bytes of data.
64 bytes from 10.10.58.175:  icmp_seq=1 ttl=57 time=3.52 ms
64 bytes from 10.10.58.175: icmp_seq=2 ttl=57  time=2.88 ms
  
---  10.10.58.175 ping statistics ---
2 packets transmitted, 2 received, 0% packet  loss, time 999ms
rtt min/avg/max/mdev = 2.886/3.204/3.522/0.318  ms

[root@puppetmaster ~]# ping mwxnsb24
ping:  unknown host mwxnsb24


Last edited by Scott; 11-24-2011 at 03:14 AM.. Reason: Removed formatting, change quote to code tags
# 2  
Old 11-24-2011
Hi,

may you please post the contents of /etc/nsswitch.conf, /etc/resolv.conf and /etc/hosts?

see ya

fra

Last edited by frappa; 11-24-2011 at 03:39 AM.. Reason: typo correction
# 3  
Old 11-24-2011
here you go:

/etc/nsswitch.conf:

Quote:
#hosts: db files nisplus nis dns
hosts: files dns
bootparams: nisplus [NOTFOUND=return] files

ethers: files
netmasks: files
networks: files
protocols: files
rpc: files
services: files

netgroup: nisplus
publickey: nisplus
automount: files nisplus
aliases: files nisplus
/etc/resolv.conf:

Quote:
[root@puppetmaster ~]# cat /etc/resolv.conf
; generated by /sbin/dhclient-script

search prod.nyxxx.com nyxxx.com
nameserver 10.11.49.206
nameserver 10.10.50.206
/etc/hosts:
Quote:
[root@puppetmaster ~]# cat /etc/hosts
# HEADER: This file was autogenerated at Wed Oct 05 18:38:36 -0400 2011
# HEADER: by puppet. While it can still be managed manually, it
# HEADER: is definitely not recommended.
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
#192.168.11.60 puppetmaster.nyfix.selab.local puppetmaster
192.168.10.181 puppetmaster.nyfix.selab.local puppetmaster
192.168.11.65 puppetclient.nyfix.selab.local puppetclient
if I place the hostname in /etc/hosts its pingable.
# 4  
Old 11-24-2011
Hi,

config files seem ok.
Googling around it seems somebody also experienced similar issues; not clear if and how they cleared the problem though..

First thing you could try to exclude problems with the internal nameservers you are using.
If you can, try reproduce the problem by ping/nslookup to an external site (i.e.: www. google.com).
If the above can be done, try also to use some external dns server (i.e. opendns) and repeat the test against an external host (i.e. www. google.com again).

If you can execute the above tests and if the results of the above tests replay the problem already posted, we can exclude a problem with internal dns servers.


Next thing I could suggest is verifying the shared libraries used by nslookup and by ping:
this can be done by:
- looking for the full paths to nslookup and ping:
Code:
which nslookup
which ping

- then listing the shared libraries to check for problems:
Code:
ldd -v /path/to/nslookup
ldd -v /path/to/ping

and verifying that the required libraries are actually available (in particular, the libdns* and libresolv* ones).

I may also suggest the following forum:
Weird ping issue on redhat box - Page 2 - [H]ard|Forum
the user ScYcS experienced similar problem, you could contact her/him directly to kow if and how he cleared the issue.

see ya
fra

Last edited by frappa; 11-24-2011 at 04:59 AM.. Reason: removed urls to google.com, only string values needed
This User Gave Thanks to frappa For This Post:
# 5  
Old 11-25-2011
here's what i have done so far:
- Reverse the order "files dns" in /etc/nsswitch.conf and /etc/host.conf to have proper search as well
- Verified shared libraries of ping and nslookup using ldd -v /path/to/ping and verified that the required libraries are actually available (in particular, the libdns* and libresolv* )
- Tried to switch off network_ipv6 in /etc/sysconfig/network
- Interchange IP address of eth0 and eth1
- Even turn off the iptables firewall service to make sure there is no something blocking from the firewall
- I can dig the clients and get the proper replies
- I can nslookup and get the proper replies
Still, haven't figured it out yet

Btw, my OS is Redhat 5.4 and it is a vm machine.

Last edited by linuxgeek; 11-25-2011 at 05:01 AM..
# 6  
Old 11-25-2011
Hi,

just for sake of completeness: did you experience this issue after an update/installazion of obsolete/new software, just after installation or all of a sudden?

see ya
fra
# 7  
Old 11-25-2011
there is no new updates/installation of software or packages. The server is in lab environment and what is newly configured is NAT to connect it in production network. now, it is connected to prod by pinging the IP address of servers but can't ping by hostname. already exported the dns servers from prod network to the server but still encountered the same.
Code:
[root@puppetmaster ~]# nslookup mwxnsb24
Server:         10.11.49.206
Address:        10.11.49.206#53

Name:   mwxnsb24.nyxxx.com
Address: 10.10.58.175

[root@puppetmaster ~]# ping mwxnsb24

Code:
[root@puppetmaster ~]# iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere            state RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             anywhere

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination


Last edited by pludi; 11-25-2011 at 01:16 PM..

Previous Thread | Next Thread
Test Your Knowledge in Computers #688
Difficulty: Medium
The first computer to implement architectures enabling reverse Polish notation (RPN) was the Apple I computer.
True or False?

10 More Discussions You Might Find Interesting

1. IP Networking

DNS problem : ping doesn't recognize hostname

I have vmware on my windows PC ( hostname : acer ). vmware has RHEL 7 ( hostname : rhel7 ) installed recently. RHEL IP configuration IP : 192.168.5.128 Netmask : 255.255.255.0 ssh to rhel7 works from acer using putty resolve.conf cat /etc/resolv.conf nameserver 192.168.5.1 host... (12 Replies)
Discussion started by: hiten.r.chauhan
12 Replies

2. Red Hat

Nslookup working but ping not working at windows client

Hi Team we have created a DNS server at RHEL6.2 environment in 10.20.203.x/24 network. Everything is going well on linux client as nslookup, ping by host etc in entire subnet. We are getting problem in windows client as nslookup working as well but not ping. all the firewall is disabled and... (5 Replies)
Discussion started by: boby.kumar
5 Replies

3. Shell Programming and Scripting

Ping the hostname of many servers using a script

Hi We have some 300 servers in the Data center and some of them are running with AIX and some of them are running with Solaris. I need a script which can be run in one of the server and that script should ping the hostname of all the 300 servers. Also the script should notify if any server is... (9 Replies)
Discussion started by: newtoaixos
9 Replies

4. Solaris

my sun solaris 10 cannot ping and nslookup other server using hostname.

hi.... i have sun solaris 10 server, fedora 10, and Windows Server.. i cant ping my sun solaris 10, fedora 10 and Windows Server using hostname (etc: ping winserver.bengkel2.com), but i can ping all using IPV4 and IPV6 address.. can u give some suggestion to solve my problem or some idea to... (3 Replies)
Discussion started by: izuan_7657
3 Replies

5. UNIX for Dummies Questions & Answers

Suse 10 SP3 won't ping hostname

hi guys I got something I haven't been able to fix I configure a Linux Suse 10 box, added static IP, DNS (resolv), gateway (routes) but I am not able to ping other servers by name but nslookup works and the server can navigate on internet check below the problematic server is server-host20 ... (4 Replies)
Discussion started by: kopper
4 Replies

6. AIX

Ping by hostname

Hello everyone I have a partition with a problem with ping. If I do a ping by ip for example ping 1.1.1.1 I got no problem but If I ping by hostname for example ping partition1 take almost a minute to respond me. I have Aix 5.3 and I have another 19 partitions with no problem. The only... (5 Replies)
Discussion started by: lo-lp-kl
5 Replies

7. Solaris

Can't ping using hostname on Solaris 10

I recently installed Solaris 10 on my Sun workstation. I cannot ping using hostname from another computer on the same network. But I can ping using the IP address. Also I can ping other systems using their hostnames. Can anyone give some information regarding how to resolve this issue. (4 Replies)
Discussion started by: alpha123
4 Replies

8. Solaris

cannot ping by hostname

Hi All, My current setup is: 1x Windows Server (Windows 2000 server) 1x Unix Server 2x Windows machine 3x Unix Terminals (Hostnames = A, B and C) Problem The problem iam having is Unix terminal C cannot be ping across by Unix terminal A or B or Unix server by using the hostname. Unix... (1 Reply)
Discussion started by: tlee
1 Replies

9. HP-UX

UX 11iV2 - No ping by hostname

Hi. I just installed the HP-UX 11i V2. I have problems with CDE - it is inoperative (after logon there is a message box: messaging system failure - or something like that, it asks to check /etc/hosts and network settings). nslookup works by hostname and IP, hostname shown the correct... (7 Replies)
Discussion started by: netwalker
7 Replies

10. Solaris

ping -s not working

I have a multipath system with 2 physicals, a virtual and a failsafe. All network connectivity is working fine to and from all of the interfaces and the virtual. The one thing that is not working is 'ping -s'. From this machine, I cannot send and receive packets using ping -s. ping without the... (1 Reply)
Discussion started by: tjlst15
1 Replies

Featured Tech Videos