topic Re: Telnet Issue from IMC to a particular switch in IMC

Telnet Issue from IMC to a particular switch

brillient — Thu, 24 Sep 2020 04:21:31 GMT

Hi,

Having trouble backup up one particualar switch with HP IMC.

I have a number of HP/Aruba 2910's and 2920's that I manage with IMC. Config backups are working on all but one 2920.

The error I get is "Failed to telnet the device".

I can manually telnet to this device OK.

The version of IMC is 7.1

Any ideas on what is going wrong?

Thanks

Re: Telnet Issue from IMC to a particular switch

brillient — Thu, 24 Sep 2020 04:28:48 GMT

solved

Re: Telnet Issue from IMC to a particular switch

techin — Thu, 24 Sep 2020 05:34:07 GMT

@brillient

How? Can you give more details..how you fixed it

Re: Telnet Issue from IMC to a particular switch

jguse — Fri, 25 Sep 2020 09:49:27 GMT

Hello,

If telnet works separately from the iMC system to the device, it was probably an issue with the telnet credentials in iMC not matching those used on the device. You can check on the Device Details via Configure > Modify Telnet Settings. There is a Test button which can be used to check if the login works.

If it doesn't, since telnet is plaintext, you can easily capture and analyze the telnet packets using Wireshark on the iMC server. Make sure iMC is able to access the manager or "enable" prompt on the device.

Re: Telnet Issue from IMC to a particular switch

Tim Gowen — Tue, 06 Oct 2020 15:03:58 GMT

I am researching a similar problem. My switch it set up for SSH login but when I try and deploy an update I am getting failures:

1.Please check the Telnet user name and password are correct.
2.Please check the Telnet software exists in system.
3.VTY is out of limit of device, please try later.

The switch is Aruba 2930M 48G PoE+ 1-slot Switch. Switch, revision WC.16.07.0003, ROM WC.17.02.0006.

This has worked with SSH before on other switches. What can I do to troubleshoot?

Re: Telnet Issue from IMC to a particular switch

jguse — Tue, 06 Oct 2020 15:19:26 GMT

Hello,

You could start by manually connecting to your switch with SSH using Putty or similar from the IMC system. If that works and you are able to log in, check the SSH settings in IMC and make sure the credentials work (like with Telnet settings, there is a "Test" button you can use).

If the manual SSH already fails, you should check on the switch side. Could be that there are too many open sessions already (show session-list) and this is preventing IMC from logging in - that's what the tip "VTY is out of limit of device, please try later." is referring to. You can also look in the switch log for errors.

There have been issues in past iMC versions where the SSH sessions to some devices did not get closed properly when iMC was done - if you run into that, upgrading iMC would be a good idea.