Can not ping/telnet/ftp from our box to any other box on our network

Can not ping/telnet/ftp from our box to any other box on our network

Post by Chri » Thu, 14 Feb 2002 08:40:37



Hi. I just inherited a 2.6 box that has some one odd networking issue:
We can not ping/telnet/ftp from our box to any other box on our network.

When we try to ping, nothing happens & it comes back with the message:
 ping: unknown host suntan (where suntan is the box we are trying to ping)

o The host does exist. Other boxes next to this box can see/ping the host

o This is a *relative* new install: 5.6 Generic_105181-29
   SUNW,SPARCstation-20 o arp sun1 => sun1 (138.2.120.183) at
     8:0:20:63:41:a5 permanent published

o ifconfig -a , shows that it is UP

o From the box, we can not ping by IP. When we do it just hangs/goes blank &
goes no where.

o When we ping -s from another box to our sun1 box:
  PING Statistics----
 7 packets transmitted, 0 packets received, 100% packet loss
 When we ping -s from our sun1 box to another box: PING Statistics----
 111 packets transmitted, 0 packets received, 100% packet loss

o This is what our nsswitch.conf looks like:
   passwd: files group: files
   hosts: files dns
   networks: files
   protocols: files
   rpc: files
   ethers: files
   netmasks: files
   bootparams: files
   publickey: files
   netgroup: files
   automount: files

 Here is our /etc/inet/hosts table # 127.0.0.1 localhost loopback
     138.2.120.183 sun1 sun1.us.xyz.com
 # more resolv.conf domain us.xyz.com
   options retry:1
   options retrans:2
   nameserver 138.2.211.15
   nameserver 130.35.249.20
   nameserver 130.35.249.21
   search us.xyz.com

** If we telnet to another box, it will pick up the ip address, but go
 nowhere: telnet suntan Trying 138.1.160.77...

Any further ideas?

Thanks!
-Chris D.

 
 
 

Can not ping/telnet/ftp from our box to any other box on our network

Post by Magnus K » Thu, 14 Feb 2002 09:00:18


On 12 Feb 2002 15:40:37 -0800


> Hi. I just inherited a 2.6 box that has some one odd networking issue:
> We can not ping/telnet/ftp from our box to any other box on our network.

> When we try to ping, nothing happens & it comes back with the message:
>  ping: unknown host suntan (where suntan is the box we are trying to ping)

> o The host does exist. Other boxes next to this box can see/ping the host

> o This is a *relative* new install: 5.6 Generic_105181-29
>    SUNW,SPARCstation-20 o arp sun1 => sun1 (138.2.120.183) at
>      8:0:20:63:41:a5 permanent published

> o ifconfig -a , shows that it is UP

> o From the box, we can not ping by IP. When we do it just hangs/goes blank &
> goes no where.

> o When we ping -s from another box to our sun1 box:
>   PING Statistics----
>  7 packets transmitted, 0 packets received, 100% packet loss
>  When we ping -s from our sun1 box to another box: PING Statistics----
>  111 packets transmitted, 0 packets received, 100% packet loss

> o This is what our nsswitch.conf looks like:
>    passwd: files group: files
>    hosts: files dns
>    networks: files
>    protocols: files
>    rpc: files
>    ethers: files
>    netmasks: files
>    bootparams: files
>    publickey: files
>    netgroup: files
>    automount: files

>  Here is our /etc/inet/hosts table # 127.0.0.1 localhost loopback
>      138.2.120.183 sun1 sun1.us.xyz.com
>  # more resolv.conf domain us.xyz.com
>    options retry:1
>    options retrans:2
>    nameserver 138.2.211.15
>    nameserver 130.35.249.20
>    nameserver 130.35.249.21
>    search us.xyz.com

> ** If we telnet to another box, it will pick up the ip address, but go
>  nowhere: telnet suntan Trying 138.1.160.77...

> Any further ideas?

> Thanks!
> -Chris D.

Can you ping 127.0.0.1 and localhost from the box?

/magnus

 
 
 

Can not ping/telnet/ftp from our box to any other box on our network

Post by Philippe Delso » Thu, 14 Feb 2002 22:16:24


Chris a crit dans le message

Quote:>Hi. I just inherited a 2.6 box that has some one odd networking issue:
>We can not ping/telnet/ftp from our box to any other box on our network.

>When we try to ping, nothing happens & it comes back with the message:
> ping: unknown host suntan (where suntan is the box we are trying to ping)

>o The host does exist. Other boxes next to this box can see/ping the host

>o This is a *relative* new install: 5.6 Generic_105181-29
>   SUNW,SPARCstation-20 o arp sun1 => sun1 (138.2.120.183) at
>     8:0:20:63:41:a5 permanent published

>o ifconfig -a , shows that it is UP

>o From the box, we can not ping by IP. When we do it just hangs/goes blank
&
>goes no where.

>o When we ping -s from another box to our sun1 box:
>  PING Statistics----
> 7 packets transmitted, 0 packets received, 100% packet loss
> When we ping -s from our sun1 box to another box: PING Statistics----
> 111 packets transmitted, 0 packets received, 100% packet loss

>o This is what our nsswitch.conf looks like:
>   passwd: files group: files
>   hosts: files dns
>   networks: files
>   protocols: files
>   rpc: files
>   ethers: files
>   netmasks: files
>   bootparams: files
>   publickey: files
>   netgroup: files
>   automount: files

> Here is our /etc/inet/hosts table # 127.0.0.1 localhost loopback
>     138.2.120.183 sun1 sun1.us.xyz.com
> # more resolv.conf domain us.xyz.com
>   options retry:1
>   options retrans:2
>   nameserver 138.2.211.15
>   nameserver 130.35.249.20
>   nameserver 130.35.249.21
>   search us.xyz.com

>** If we telnet to another box, it will pick up the ip address, but go
> nowhere: telnet suntan Trying 138.1.160.77...

>Any further ideas?

>Thanks!
>-Chris D.

Are sun1 (138.2.120.183) and suntan (138.1.160.77) on the same network.

Check the routing table (netstat -r).

Philippe

 
 
 

Can not ping/telnet/ftp from our box to any other box on our network

Post by Chri » Fri, 15 Feb 2002 02:00:43


Quote:

> Can you ping 127.0.0.1 and localhost from the box?

> /magnus

Yes I can.  
  o  Ping 127.0.0.1  works correctly
  o  Ping localhost  works correctly
  o  Ping any other box, nothing happens

Thanks!
-Chris D.

 
 
 

Can not ping/telnet/ftp from our box to any other box on our network

Post by Vlad » Fri, 15 Feb 2002 11:34:52



Quote:

>> Can you ping 127.0.0.1 and localhost from the box?

>> /magnus

> Yes I can.  
>   o  Ping 127.0.0.1  works correctly
>   o  Ping localhost  works correctly
>   o  Ping any other box, nothing happens

> Thanks!
> -Chris D.

Check the file /etc/nsswitch.conf
Basically this file among other things, indicates the order in which
hostnames will be resolved. For example, according the file, a hostname
could be attempted to be resolved through files(/etc/hosts), rather then
dns.
You job is to make sure that the file /etc/nsswitch.conf shows the proper
order of resolution.

The following is a fragment of that file :

# An example file that could be copied over to /etc/nsswitch.conf; it
# does not use any naming service.
#
# "hosts:" and "services:" in this file are used only if the
# /etc/netconfig file has a "-" for nametoaddr_libs of "inet" transports.

passwd:     files
group:      files
hosts:      files       dns
networks:   files
protocols:  files
rpc:        files
ethers:     files

As you can see, hosts are resolved through files and then if not found,
through dns. If you don't have that, the system looks up /etc/hosts,
doesn't find the name there, and can't connect (even if physical
connectivity is present)

I hope I helped you a bit...

 
 
 

Can not ping/telnet/ftp from our box to any other box on our network

Post by Chri » Sun, 17 Feb 2002 04:56:48


Quote:> Check the file /etc/nsswitch.conf
> I hope I helped you a bit...

Yes!  It now works!!!  That help provide the answer.  Inside the
nsswitch.conf file, just out of curiosity I made the following change:

From:
     hosts:      files       dns
To:
     hosts:      dns       files

It worked from that moment on.  Thank you very much for your help!!!

Thank you
-Chris D.