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Re: ping to port not working, 3 NICs,

 
Steve Lewis
Honored Contributor

Re: ping to port not working, 3 NICs,

OK since you can telnet and ping from another server on the same subnet, but not from your PC, then your PC has no route to the host.
On your PC type:
traceroute 10.1.236.233
and see if it can reach the server.

If it cannot get there, then ask your network administrator to connect it up and define a route from your switch/router.

Remember, only traffic that needs to get to that IP/interface should get to that IP/interface. Other users can connect via the other IPs. Its all to do with your your goals are.

jamesps
Regular Advisor

Re: ping to port not working, 3 NICs,

What is your PC IP address? You probably have a router in between which does the routing to these 3 different subnets right? The routing is obviously not an issue since the packets are going to the server and back successfully. Is there a firewall (packet filter) in between which can filter out this port 8007?

If you do a telnet while locally connected on that server does it work?
Basheer_2
Trusted Contributor

Re: ping to port not working, 3 NICs,

Yes
tracert from my pc works ok
telnet from the server to that ip works ok, i get the login.
jamesps
Regular Advisor

Re: ping to port not working, 3 NICs,

If telnet locally on that server works then the only problem I see remains with the traffic being blocked from your PC to that IP address. Is there a way to plug in your PC in that subnet to confirm this?
Can you check the firewall logs to see if your telnet is being blocked?
Basheer_2
Trusted Contributor

Re: ping to port not working, 3 NICs,

Thanks James
I have anohter server on 10.1.236.x
from there i can ping and telnet
jamesps
Regular Advisor

Re: ping to port not working, 3 NICs,

Do you have some firewall locally on your PC? Is it a Windows PC? Can you do a "netstat -an" on your PC right after trying to telnet to that server again?

Have you tried changing your PC IP address in the 10.1.236.0 network, for example assign to it the same IP address which is assigned to the other server on which the telnet works. After disconnecting that one from the network first of course.
rick jones
Honored Contributor

Re: ping to port not working, 3 NICs,

Strictly speaking, one is allowed to configure multiple physical NICs into the same IP subnet. Just keep in mind that by default, it is assumed by the transport that all the NICs in the same IP subnet have the same connectivity because while traffic will be received on all the NICs, it will only go out one of them.

You can use ip_strong_es_model with a value of 1 or 2 to cause source IP to be included in route selection, which will have the effect of generally causing traffic to go out the same NIC on which it arrived - there is more to it than just that though.
there is no rest for the wicked yet the virtuous have no pillows
Basheer_2
Trusted Contributor

Re: ping to port not working, 3 NICs,

Thanks Rick

can you tell me how to set that value and where
rick jones
Honored Contributor

Re: ping to port not working, 3 NICs,

man ndd :) to make it stick you edit /etc/rc.config.d/nddconf

you should search the rest of the forums for discussions involving ip_strong_es_model for all the caveats and such.

the "best" way to have multiple NICs in the same IP subnet though is the aforementioned use of Auto Port Aggregation...
there is no rest for the wicked yet the virtuous have no pillows
Basheer_2
Trusted Contributor

Re: ping to port not working, 3 NICs,

Thanks Rick,

my purpose here is to
1) config 3 NIC's with difft IPs
2) able to telnet into each one

Why I am not able to telnet to 3rd one.
I swapped IP address, still the same problem
with the 3rd one.
Ninad_1
Honored Contributor

Re: ping to port not working, 3 NICs,

Basheer,

From the long going discussion I observe that you can ping and telnet from 10.1.236.50 to 10.1.236.233.
From your PC you can ping but not telnet.
Lets try to eliminate some known problems from whatever you have tried uptill now.
1. Routing not proper - but since ping worked, it means routing is proper.
2. Network traffic problem - ping works and telnet does not work is common when there is heavy network traffic on the subnet. - Try ping for a longer period and see if there is 0% packet loss - try
ping 10.1.236.233 -n 25 (from 10.1.236.50 server)
From your PC also try ping for a longer time, let us know the results.
3. Firewall ports not opened - This is also possible - check with your networks team if telnet is blocked from other networks to 10.1.236.233 (Because uptill now you have succeded to telnet on the same subnet only)

Also please attache following outputs

netstat -s
netstat -in
netstat -nr

Regards,
Ninad