# No matching cipher found:

**URL:** <https://legacy-community.ine.com/t/no-matching-cipher-found/970>\
**Category:** Networking\
**Tags:** networking, security\
**Created:** [August 18, 2021, 3:01pm UTC](https://legacy-community.ine.com/t/no-matching-cipher-found/970 "2021-08-18T15:01:13Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![makintola-29926b65fe](https://avatars.discourse-cdn.com/v4/letter/m/977dab/32.png) [@makintola-29926b65fe](https://legacy-community.ine.com/u/makintola-29926b65fe)\
**Post date:** [August 18, 2021, 3:01pm UTC](https://legacy-community.ine.com/t/no-matching-cipher-found/970/1 "2021-08-18T15:01:13Z")

</div>

Hello everyone/@kbogart-81b6c89deee9,

I get this error on my switch log, I have couple of users logging in regularly.

64529: No matching cipher found: client [aes128-gcm@openssh.com](mailto:aes128-gcm@openssh.com),chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr server aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc

One research showed client is using aes128-ctr while the server is aes128-cbc, and causing a mismatch.

Kindy help for possible solutions.

Regards.

---

<div class="post-metadata">

**Author:** ![kbogart-81b6c89deee9](https://avatars.discourse-cdn.com/v4/letter/k/4af34b/32.png) [@kbogart-81b6c89deee9](https://legacy-community.ine.com/u/kbogart-81b6c89deee9)\
**Post date:** [August 18, 2021, 4:47pm UTC](https://legacy-community.ine.com/t/no-matching-cipher-found/970/2 "2021-08-18T16:47:53Z")

</div>

This thread on Reddit might help shed some light on this problem:

> <https://unix.stackexchange.com/questions/459074/ssh-unable-to-negotiate-no-matching-cipher-found-is-rejecting-cbc>

In short, it looks like whatever users are utilizing OpenSSH to gain SSH access into your switch need to modify their _ **/etc/ssh/sshd\_config** _ file. Most likely they’ll need to manually add AES128-CBC to their file.  
Hope that helps!  
Keith

---

<div class="post-metadata">

**Author:** ![jackyjoy826-25fa109e](https://avatars.discourse-cdn.com/v4/letter/j/f08c70/32.png) [@jackyjoy826-25fa109e](https://legacy-community.ine.com/u/jackyjoy826-25fa109e)\
**Post date:** [September 24, 2021, 12:56pm UTC](https://legacy-community.ine.com/t/no-matching-cipher-found/970/3 "2021-09-24T12:56:45Z")

</div>

> [@kbogart-81b6c89deee9](#):
>
> In short, it looks like whatever users are utilizing OpenSSH to gain SSH access into your switch need to modify their _ **/etc/ssh/sshd\_config** _ file. Most likely they’ll need to manually add AES128-CBC to their file.  
> Hope that helps!  
> Keit

thanks for the awesome information.