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
+ N8 u4 D3 R9 U  r+ f( K8 E3 w
# n% W3 ?) Q! T4 {( |  mConnecting to 192.168.2.138:22...
9 G% g+ s6 S3 E$ S/ |. i* NConnection established.
  A2 e3 j7 |" e( FTo escape to local shell, press 'Ctrl+Alt+]'.
Connection closed by foreign host.
Disconnected from remote host(192.168.2.138:22) at 10:09:49.
  S0 s1 I; E3 X* ~Type `help' to learn how to use Xshell prompt.
: C3 P( v2 h0 Q' [0 z
xshell5连接ubuntu20.10失败，提示"找不到匹配的key exchange算法"

3 q* K# `! k) d% F4 e
解决办法：
在sshd_config 文件中填加 增加ubuntu20.10 key excange算法diffie-hellman-group14-sha1，

  M% \/ N. {! F9 P
0 u+ u' X# E$ ~
6 g$ ^2 L& I- O$ |! P$ ~. secho "KexAlgorithms +diffie-hellman-group14-sha1"  >>/etc/ssh/sshd_config

; @( a% o5 C9 h; b重启sshd服务生效：
root@localhost:~# systemctl restart sshd
9 |" r* |1 j( o/ X' P" }  c
root@localhost:~# systemctl status sshd
$ N% I2 D8 w$ z/ }; a' }: T/ b● ssh.service - OpenBSD Secure Shell server
' s$ y/ d8 d2 p/ ^' t5 R     Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
     Active: active (running) since Thu 2021-11-04 02:23:05 UTC; 54s ago
* O& H- ^0 W/ n8 Z. Q& O; h; n       Docs: man:sshd(8)
             man:sshd_config(5)
8 l) d  u6 q9 }5 V- i    Process: 2005 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
7 `: j* O! i1 k5 S( k' i9 R9 M   Main PID: 2006 (sshd)
( ]2 V+ W3 M( u2 i9 A- I      Tasks: 1 (limit: 4606)
% p! e; W3 Q9 Z0 H) u     Memory: 1.3M
     CGroup: /system.slice/ssh.service
  R0 @7 {2 B, P/ o  R4 s             └─2006 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
Nov 04 02:23:05 localhost systemd[1]: Starting OpenBSD Secure Shell server...
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.

* U: G$ B. g% F" }% J$ uConnecting to 192.168.2.138:22...
# a: }! e) V' u9 W  Z! b! jConnection established.
To escape to local shell, press 'Ctrl+Alt+]'.
7 \2 [9 t4 w$ \/ a0 @1 r; U+ FWelcome to Ubuntu 20.10 (GNU/Linux 5.8.0-63-generic x86_64)
9 y8 X$ ~" V1 u- ` * Documentation:  https://help.ubuntu.com
0 }5 F* m1 R! n  d2 Q! E * Management:     https://landscape.canonical.com
$ B' O+ C1 W+ J * Support:        https://ubuntu.com/advantage
  System information as of Thu Nov  4 02:16:49 AM UTC 2021
  System load:  0.0               Processes:             134
- `+ e7 o' v# z1 Q+ x# J  Usage of /:   76.0% of 2.99GB   Users logged in:       1
  Memory usage: 5%                IPv4 address for ens3: 192.168.2.138
  Swap usage:   0%
7 y1 ?  M# o# R) f( R, m- i4 t
: [3 H( N5 y& U, Q' v76 updates can be installed immediately.
0 of these updates are security updates.
3 Z, d7 g* u- e* yTo see these additional updates run: apt list --upgradable
/ I( w: E6 e. g" u  K8 IYour Ubuntu release is not supported anymore.
For upgrade information, please visit:
http://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:~$
" N% G- S: d9 M
8 ]7 j5 _! t5 l: l8 h