- Community Home
- >
- Servers and Operating Systems
- >
- Operating Systems
- >
- Operating System - Linux
- >
- Telnet Sessions Suddenly Lost
Categories
Company
Local Language
Forums
Discussions
Forums
- Data Protection and Retention
- Entry Storage Systems
- Legacy
- Midrange and Enterprise Storage
- Storage Networking
- HPE Nimble Storage
Discussions
Discussions
Discussions
Forums
Discussions
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
- BladeSystem Infrastructure and Application Solutions
- Appliance Servers
- Alpha Servers
- BackOffice Products
- Internet Products
- HPE 9000 and HPE e3000 Servers
- Networking
- Netservers
- Secure OS Software for Linux
- Server Management (Insight Manager 7)
- Windows Server 2003
- Operating System - Tru64 Unix
- ProLiant Deployment and Provisioning
- Linux-Based Community / Regional
- Microsoft System Center Integration
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Community
Resources
Forums
Blogs
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-07-2013 05:28 AM - last edited on 06-09-2013 11:29 PM by Maiko-I
06-07-2013 05:28 AM - last edited on 06-09-2013 11:29 PM by Maiko-I
Telnet Sessions Suddenly Lost
Hello
I have the following setup
1 Hp Small Business Server
1 Hp server running sco
Approx 30 PC's
8 printers
All connected via a 10gb network
This setup has been runnig without problems for 6 years
The PCs connect to the sco server using telnet/TUN
For the last month two or three times a day the PCs lose connection to the sco server with the message 'connection closed by foreign host'. Access to the Small Business Server is unaffected.
Sometimes one or two lose connection, sometimes all of them. The applications on the sco server continue to run and have to be killed off manually.
Any ideas?
Thanks in antcipation.
Mosaix
P.S. This thread has been moved from HP-UX > System Administration to Linux > networking - Hp Forum moderator
- Tags:
- telnet
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-08-2013 12:41 AM - edited 06-08-2013 12:41 AM
06-08-2013 12:41 AM - edited 06-08-2013 12:41 AM
Re: Telnet sessions suddenly lost
What HP-UX version are you using?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-08-2013 01:24 AM
06-08-2013 01:24 AM
Re: Telnet sessions suddenly lost
Hi
Thanks for replying.
The Small Business Server is Windows based. The Unix server is running SCO rather than HP-UX.
Mosaix
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-10-2013 12:30 AM
06-10-2013 12:30 AM
Re: Telnet Sessions Suddenly Lost
> For the last month two or three times a day the PCs lose connection to the sco server with the message 'connection closed by foreign host'. Access to the Small Business Server is unaffected.
So, for the client PCs, it looks like the SCO server is closing the connections.
Are there any log messages on the SCO server when a connection is lost?
If the SCO server logs say that the client is closing or resetting the connection, then there might be a firewall or a NAT device between the server and the clients. Such devices often maintain a table of existing connections. To protect against various types of attack, existing connections are allowed through only if a matching connection entry already exists in the table. When a new connection is established in the proper way, a new entry is added.
Because the resources of the firewall/NAT device are not infinite, those devices need to clean out old entries from their connection table. Sometimes this clean-up can be a bit overzealous. For example, if no data has transferred over a particular connection in a certain number of minutes, the connection may be cleaned up. At that point, both ends of the connection will see it as the opposite end closing the connection, while it is actually the firewall/NAT box that does the closing.
If many connections are lost at once, it might be that the firewall/NAT device is crashing and rebooting, or it is being reconfigured and needs to flush its connection table.
- Tags:
- firewall
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-10-2013 03:07 AM
06-10-2013 03:07 AM
Re: Telnet Sessions Suddenly Lost
Matti
Many thanks for your reply. I will investigate your suggestion and report back.
Many thanks.
Mosaix
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-12-2013 05:36 AM
06-12-2013 05:36 AM
Re: Telnet Sessions Suddenly Lost
Matti (and anyone else who gave this any thought) many thanks.
Problem solved.
I keep a diary of any significant events in the system (software upgrades, new hardware etc) and I'd gone back through this to the day the problems started without any luck.
Yesterday was the worst day of all, the HP SCO server was off the network for 6 hours resulting in considerable loss of business.
In the end I rebooted it. I started a ping on another system to show me when it had come up but, to my surprise, the ping responded immediately. There was insufficient time for the system to have rebooted. There was another device on the network with the same IP address!
Afetr much investigation another department had installed a remote system at another site and the suppliers had given it a fixed IP address - the same as the SCO server. These suppliers were the same ones who had refused to help with the problem!
Anyway thought I'd post this here to help anyone else with a similar problem in the future.
Again many thanks.
Mosaix