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With new OpenSSH Client 7.1: No "normal" SSH Login to EXOS possible

With new OpenSSH Client 7.1: No "normal" SSH Login to EXOS possible

SchmuFoo
Contributor
Hello,

with the current OpenSSH Client 7.1 (released August 21, 2015) it is not possible any longer to login "directly" to an EXOS switch.

~ $ ssh admin@X
Unable to negotiate with X: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1
According to http://www.openssh.com/legacy.html the workaround is:

~ $ ssh admin@X -oKexAlgorithms=+diffie-hellman-group1-sha1 -oHostKeyAlgorithms=+ssh-dss
[..]
Enter password for admin:
ExtremeXOS
Copyright (C) 1996-2015 Extreme Networks. All rights reserved.
This product is protected by one or more US patents listed at http://www.extremenetworks.com/patents along with their foreign counterparts.
==============================================================================
Press the or '?' key at any time for completions.
Remember to save your configuration changes.
Slot-1 Y #

Are there any plans or already ways, that EXOS's SSH Implementation doesn't use weak/legacy algorithms?

Cheers
Jan

P.S.: Tested with EXOS up to:

# sh version
Switch : 800551-00-05 1523N-44609 Rev 5.0 BootROM: 1.0.2.1 IMG: 16.1.1.4
X460-G2-VIM-2X-B-1: 800556-00-03 1502N-42815 Rev 3.0
PSU-1 : Internal PSU-1 800592-00-07 1519A-45753
PSU-2 : Internal PSU-2 800592-00-07 1519A-45758
Image : ExtremeXOS version 16.1.1.4 by release-manager
on Fri Jun 12 17:47:56 EDT 2015
BootROM : 1.0.2.1
Diagnostics : 3.1
7 REPLIES 7

ECOMMERCE_lucas
New Contributor
Are there any updates on this topic?

Stephane_Grosj1
Extreme Employee
Hi,

yes, there're plans to upgrade the SSH Server in future release. It doesn't seem we can have stronger key exchange methods in our current implementation.

Drew_C
Valued Contributor III
This sounds like something we'll need to look into. I'll do some checking internally, and I suspect someone may be able to come back with more information before I can.

Can I ask what OS you're using?
GTM-P2G8KFN