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Unable to access Switch after reboot

Problem description: I have a Cisco Switch C4500X-16, which got rebooted about 2 weeks ago. After the reboot, the switch came back up and everything is working fine, to only thing is, I'm not able to access it remotely (via SSH directly to the switch). I have local user authentication and use SSH version 2 to access it remotely. However, if I access another switch that is connected to this one, and try to ssh -l, I'm able to access the switch. If I try to access it via SSH directly, it doesn't even give me a login prompt. 

 

8 Replies 8

can you share the configurations related to VTY lines

Please rate this and mark as solution/answer, if this resolved your issue
Good luck
KB

VTY

line vty 0 4
privilege level 15
transport input ssh
line vty 5 15
privilege level 15
!

Sh ip ssh

sh ip ssh
SSH Enabled - version 1.99
Authentication methods:publickey,keyboard-interactive,password
Authentication Publickey Algorithms:x509v3-ssh-rsa,ssh-rsa
Hostkey Algorithms:x509v3-ssh-rsa,ssh-rsa
Encryption Algorithms:aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc,aes128-ctr,aes192-ctr,aes256-ctr
MAC Algorithms:hmac-sha1,hmac-sha1-96
Authentication timeout: 120 secs; Authentication retries: 3
Minimum expected Diffie Hellman key size : 1024 bits
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAYQCZ6daLhzy7D3m49NHox7/esbIXL+sWuT1j0xUebTIq
sHRweX2AfoaOIcqzQi5K21WrK9tT/I5s/2imOgRMU3rAQbBuZBK+A55RCZ9UCEVFDmn2mySNzWEccgih

is your PC can ping to switch management IP? is switch accessible from PC? are you getting connection reset error or unable to connect error when doing SSH?

Please rate this and mark as solution/answer, if this resolved your issue
Good luck
KB

I'm not able to reach the switch management IP from my PC. Switch 2, however, is reachable and I can ping it from my PC. I'm using Putty, the error that I get is the following: 

carlosrodriguez17_0-1674555639511.png

 

marce1000
VIP
VIP

 

   >... If I try to access it via SSH directly, it doesn't even give me a login prompt. 
                        How far do you get then ? (and or post a screenshot (e.g.))
 M.



-- Each morning when I wake up and look into the mirror I always say ' Why am I so brilliant ? '
    When the mirror will then always repond to me with ' The only thing that exceeds your brilliance is your beauty! '

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@carlosrodriguez17 wrote:
if I access another switch that is connected to this one, and try to ssh -l, I'm able to access the switch.

ACL

what IP you use in PC ? what is IP of managment VLAN ?
I think that direct not work because the IP of PC is different subnet than the management VLAN IP. 
when you access via other SW success because the SW1 management VLAN IP is in same subnet of SW2 management VLAN IP

khorram1998
Level 1
Level 1

There are a few things that could be causing the issue with not being able to access the Cisco switch remotely via SSH.

  1. Check the switch's IP address and make sure that it is correct and able to be reached on the network.
  2. Check the switch's SSH configuration and ensure that it is set up to allow remote access.
  3. Ensure that the switch's local user authentication is still configured correctly and that the user account you are trying to use still exists and has the correct permissions.
  4. Check the switch's firewall settings and ensure that it is not blocking incoming SSH connections.
  5. Check the switch's logs to see if there are any error messages related to SSH or remote access.

Alternatively, you can try these commands:

Check the switch's IP address:

 

show ip interface brief

 

Check the switch's SSH configuration:

 

show running-config | include ssh

 

Ensure that the switch's local user authentication is still configured correctly:

 

show running-config | include username

 

Check the switch's firewall settings:

 

show ip access-list

 

Check the switch's logs:

 

show logging

 

If you are still unable to access the switch, it may be worth trying to reset the switch to its factory defaults and reconfigure it:

 

erase startup-config
reload

 

Please note that these commands may slightly differ depending on the IOS version you are using on your switch.

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