xshell5连接ubuntu20.10失败，提示"找不到匹配的key exchange算法"

admin

[d:\~]$ ssh 192.168.2.138
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Connecting to 192.168.2.138:22...
Connection established.
To escape to local shell, press 'Ctrl+Alt+]'.
* M/ Q( I+ }! K' z+ K& p$ c6 iConnection closed by foreign host.
8 U' _8 D1 O8 u1 O! s5 M  yDisconnected from remote host(192.168.2.138:22) at 10:09:49.
& o/ V1 M7 ]. a- UType `help' to learn how to use Xshell prompt.
7 h; ~! ^& f" E! F
. G$ K' S7 u8 c/ U; p8 Fxshell5连接ubuntu20.10失败，提示"找不到匹配的key exchange算法"


7 e2 a- r0 C3 c6 f) G% [2 C" y, Y0 W解决办法：
, W9 Q# E6 Q/ b5 U2 p- F在sshd_config 文件中填加 增加ubuntu20.10 key excange算法diffie-hellman-group14-sha1，
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! u7 K# a, g& o3 d4 s# L) W2 Z3 w, Hecho "KexAlgorithms +diffie-hellman-group14-sha1"  >>/etc/ssh/sshd_config
/ z/ ~, ]. f" X" Z( Q$ f
重启sshd服务生效：
) [- p- u1 w# k" v4 Q  q: F% S! sroot@localhost:~# systemctl restart sshd
/ E0 ~5 U0 ^6 E- |% S! j
" N5 P5 U* e5 f' O# {root@localhost:~# systemctl status sshd
● ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
5 @. h( |' [0 c     Active: active (running) since Thu 2021-11-04 02:23:05 UTC; 54s ago
       Docs: man:sshd(8)
             man:sshd_config(5)
! Z4 z. `5 p' n) p    Process: 2005 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
5 O. Q  j  l7 E& |" H+ J   Main PID: 2006 (sshd)
      Tasks: 1 (limit: 4606)
) e* m2 @9 Y2 e, {     Memory: 1.3M
     CGroup: /system.slice/ssh.service
/ f5 E' |9 \7 `* n; W) B+ H, [3 z% u. d             └─2006 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
! y; j1 V# y: f5 `7 O: K6 q( X! yNov 04 02:23:05 localhost systemd[1]: Starting OpenBSD Secure Shell server...
" R  @" P  [2 h+ \0 L: ^Nov 04 02:23:05 localhost sshd[2006]: Server listening on 0.0.0.0 port 22.
Nov 04 02:23:05 localhost sshd[2006]: Server listening on :: port 22.
Nov 04 02:23:05 localhost systemd[1]: Started OpenBSD Secure Shell server.

Connecting to 192.168.2.138:22...
6 Z2 v: i6 c/ J9 MConnection established.
$ I( ~, q7 |# {1 y2 @6 mTo escape to local shell, press 'Ctrl+Alt+]'.
Welcome to Ubuntu 20.10 (GNU/Linux 5.8.0-63-generic x86_64)
* Documentation:  https://help.ubuntu.com
* Management:     https://landscape.canonical.com
* Support:        https://ubuntu.com/advantage
7 u8 I1 R2 j* e' T* n( T  System information as of Thu Nov  4 02:16:49 AM UTC 2021
& w- z0 a+ `$ H# d7 H+ g  System load:  0.0               Processes:             134
  Usage of /:   76.0% of 2.99GB   Users logged in:       1
  Memory usage: 5%                IPv4 address for ens3: 192.168.2.138
% a% m+ a, C, w% E3 f+ o0 @  Swap usage:   0%
4 @) b9 S/ g0 P; c4 s; G' e$ Y
7 M) x! B- @0 v6 u7 u6 ~' \76 updates can be installed immediately.
0 of these updates are security updates.
To see these additional updates run: apt list --upgradable
Your Ubuntu release is not supported anymore.
For upgrade information, please visit:
) j/ }5 r+ T  q( L9 w* Ihttp://www.ubuntu.com/releaseendoflife
New release '21.04' available.
Run 'do-release-upgrade' to upgrade to it.

Last login: Thu Nov  4 02:06:54 2021
ubuntu@localhost:~$
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