topic Re: Intermittent loss of connectivity. in Operating System - HP-UX

Intermittent loss of connectivity.

Amruth — Fri, 14 Jan 2005 12:52:58 GMT

Gurus,

I have a system which is in the other side of a firewall and intermittently unable to ssh to it. But when this happens i can ping the server.

Any went though a similar problem.

Thanks,
AM

Re: Intermittent loss of connectivity.

A. Clay Stephenson — Fri, 14 Jan 2005 12:57:22 GMT

The remote server may be experiencing a denial of service attack or otherwise have run out of resources. A very common cause of services not responding BUT ping still works is that inetd has died. Without knowing anything about the remote server (is it even a UNIX box?) it's not possible to help much.

Re: Intermittent loss of connectivity.

bhavin asokan — Fri, 14 Jan 2005 12:58:11 GMT

hi,

any chance to have the ip address - of host server or the router/switch connected to it - is assigned to another host/pc in the network.

regds,

Re: Intermittent loss of connectivity.

Amruth — Fri, 14 Jan 2005 13:01:42 GMT

Clay,

All servers are HP 9000 servers with 11.11 loaded.

Also, there is no errors in the other machine that any of the services are dying or anything like that. It seems to be perfect.

Thanks,
AM

Re: Intermittent loss of connectivity.

Biswajit Tripathy — Fri, 14 Jan 2005 13:29:19 GMT

Another possible cause is that the
firewall might be doing some bandwidth
management and might be dropping some
of the packets to restrict some connections
taking too much bandwidth.

Amruth,
in the other post regarding firewall, I
did ask you what type of firewall you are
running and you have not replied to that.
It would really be helpful if you give
that info in your future questions re
firewall.

Re: Intermittent loss of connectivity.

Amruth — Fri, 14 Jan 2005 15:10:17 GMT

Hi,

I do agree with you, it is something related to bandwidth. I want to confirm myself that from the system side everything is ok.

Being i have a lack of help (good people) from network team, i am unable to answer you for the second part.

Thanks anyway,
AM

Re: Intermittent loss of connectivity.

Biswajit Tripathy — Fri, 14 Jan 2005 15:20:20 GMT

Okay.. if your firewall is doing bandwidth
management, then it's definitely not IPFilter.
IPFilter does something called dynamic connection
allocation which controls number of connections
allowed per service per IP address; but once the
connection is established, it should not slow down.

BTW, if you are using IPFilter firewall and seeing
the intermediate and temporary loss of connectivity,
then let me know and I will try to figure out
what the problem is.

- Biswajit