Crypto key generate

Unanswered Question
Nov 26th, 2009


the ssh service on the supervisor engine is unavailable after each reboot, which is painful. Hence we need to re-generate an SSH key after each reboot using 'crypto key generate rsa'

Version: "bootflash:c6msfc3-pk9sv-mz.122-14.SX2.bin"

best regarsd


I have this problem too.
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glen.grant Thu, 11/26/2009 - 07:07

   Don't know what would cause that . The keys should not be wiped out and rebooting should not disrupt the SSH functionality as the keys are stored in NVRAM .  Done literally a 1000 boxes with SSH and never seen this issue.  You could look for a bug in your version  but have never seen or heard of anything like that.  I would verify your SSH config is correct and if it continues get ahold of the TAC , they might want to replace the supervisor .

hamsofiane Thu, 11/26/2009 - 11:14


Thank you for your response, i would like confirme you that i have tested with vesion sup-bootdisk:s3223-ipservicesk9_wan-mz.122-18.SXF16.bin"

and i do not have the problème after the reload , I can see that my key still in the NVRAM.

THe configuration is :

line con 0
line vty 0 4
access-class vty-acl in
login local
transport input ssh

Version: "bootflash:c6msfc3-pk9sv-mz.122-14.SX2.bin"

I do not know if the problème is in the software version or not ? I will test with this version

In the documention i see that we can storge the key :

crypto key generate rsa

[general-keys | usage-keys | signature | encryption] [label key-label] [exportable] [modulus modulus-size] [storage devicename:] [on devicename:]

could give us a correct commande permit that ?

Best regards



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