# SSH Public Key Authentication on Cisco IOS

**URL:** https://forum.networklessons.com/t/ssh-public-key-authentication-on-cisco-ios/1403
**Category:** Lessons Discussion
**Created:** [January 11, 2017, 9:59am UTC](https://forum.networklessons.com/t/ssh-public-key-authentication-on-cisco-ios/1403 "2017-01-11T09:59:22Z")
**Posts on this page:** 1
**Showing post:** 4

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### Author: ![syncope988](https://cdn-forum.networklessons.com/user_avatar/forum.networklessons.com/syncope988/32/1385_2.png) [@syncope988](https://forum.networklessons.com/u/syncope988)
#### Post date: [May 4, 2020, 7:46am UTC](https://forum.networklessons.com/t/ssh-public-key-authentication-on-cisco-ios/1403/4 "2020-05-04T07:46:14Z")

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Hi Rene and staff,  
i was doing a basic lab ipv6 with GNS3 and SSH came in front of the scene (no matter ipv4 or ipv6 in this post)  
This is the lab

 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/1/1ed1247d4d05d2ff35f2f39a51941064d60694ae.png)  
and opening SSH session from HostA to R1 led me to review crypto keys with cisco (just to remind)  
R1 configuration is

 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/3/3cddb9fa219925dc3053076c7c5c323d6698405d.png)  
Host A is toolbox  
 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/1/19a4bfcd889830be9de2bd7d27cb796aa0804d7d.png)  
 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/0/04926248cfd32de4b030ab3403fbed9833afd2d6.png)

I opened the ssh session

 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/5/54edaed6c5614085c59f7d219fafe0d62ce6c3b5.png)  
Sorry, i failed the password twice  
And exit the session

At this step, my question is about to find the public key of R1 in hostA

Going to hostA here is what i found  
(vi /root/.ssh/known\_hosts)

 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/e/ee9a4dc3e886d8e5795db70f7ee990a8ab6eee0a.png)

Going to R1 here is what i found

 ![image](https://cdn-forum.networklessons.com/uploads/default/original/2X/7/7d72bf19c60750c53f7d7670d0042ae3d2ef7147.png)

Key data on R1 seems not to match with the content of the file known\_hosts in the client hostA: that is what i want to understand  
If i am in a wrong way please tell me so i could understand  
Regards

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