CentOS升级openssh8.9

1. 安装telnet，切换为telnet登录，确保在安装ssh时能稳定连接

[root@localhost ~]# yum install xinetd telnet-server -y
[root@localhost ~]# systemctl enable xinetd 
[root@localhost ~]# systemctl enable telnet.socket
[root@localhost ~]# systemctl start telnet.socket
[root@localhost ~]# systemctl start xinetd
#安装相关依赖，编译安装必备
[root@localhost ~]# yum install  -y gcc gcc-c++ glibc make autoconf pcre-devel  pam-devel
[root@localhost ~]# yum install  -y pam* zlib*

2. 查看当前版本

[root@localhost ~]# ssh -V
OpenSSH_8.0p1, OpenSSL 1.0.2r  26 Feb 2019

3.更新openssl
[root@localhost ~]# yum update openssl
4.安装opebssh

[root@localhost ~]# systemctl status sshd   #查看sshd
[root@localhost ~]# systemctl stop sshd    #停止sshd
[root@localhost ~]# rm -rf /etc/ssh/ #清理配置文件
#查看当前openssh
[root@localhost ~]# rpm  -qa |grep  openssh
openssh-clients-6.6.1p1-31.el7.x86_64
openssh-server-6.6.1p1-31.el7.x86_64
#删除当前openssh
[root@localhost ~]# yum erase -y openssh-clients openssh-server openssh 
#安装openssh
[root@localhost ~]# yum install -y pam-devel #安装pam
[root@localhost ]# tar xf openssh-8.9p1.tar.gz #解压openssh8.9
[root@localhost ]# cd openssh-8.9p1 
#配置
./configure --prefix=/usr/ --sysconfdir=/etc/ssh --with-openssl-includes=/usr/local/include --with-ssl-dir=/usr/local/bin --with-zlib --with-md5-passwords --with-pam 
## --prefix=/usr/ 这里还是指定一下安装的目录路径;
#--sysconfdir=/etc/ssh 这里指定的配置文件的目录路径; 
#--with-openssl-includes=/usr/local/include 看上面讲一下;
# --with-ssl-dir=/usr/local/openssl 看上面讲一下;后面参数不需要调整，写上就可以啦
#安装
make && make install
[root@localhost openssh-8.9p1]# echo $? 检查，结果为0就好了
0
[root@localhost openssh-8.9p1]# cd contrib/redhat 在解压的openssh目录找到启动文件
[root@localhost redhat]# ll
总用量 48
-rw-r--r-- 1 confluence confluence    58 2月  23 19:31 gnome-ssh-askpass.csh
-rw-r--r-- 1 confluence confluence    70 2月  23 19:31 gnome-ssh-askpass.sh
-rw-r--r-- 1 confluence confluence 30082 2月  23 19:31 openssh.spec
-rwxr-xr-x 1 confluence confluence  1721 2月  23 19:31 sshd.init
-rw-r--r-- 1 confluence confluence   277 2月  23 19:31 sshd.pam
[root@localhost redhat]# cp -a sshd.init /etc/init.d/sshd
cp：是否覆盖"/etc/init.d/sshd"？#回车
#启动ssh
[root@localhost redhat]# systemctl start sshd
Warning: sshd.service changed on disk. Run 'systemctl daemon-reload' to reload units. #警告了，操作下
[root@localhost redhat]# systemctl daemon-reload #按照上面提示操作
[root@localhost redhat]# systemctl start sshd #启动
#顺便设置一下开机自动启动
#常规的 systemctl 设置会给予一个提示，命令被重定向了，那么就使用提示给的命令
[root@localhost redhat]# systemctl enable sshd
sshd.service is not a native service, redirecting to /sbin/chkconfig.
Executing /sbin/chkconfig sshd on
#再次设置开机启动
#下面显示2、3、4、5是on就可以，其数字代表启动级别
[root@localhost redhat]# /sbin/chkconfig sshd on
[root@localhost redhat]# chkconfig --list sshd

注意：该输出结果只显示 SysV 服务，并不包含原生 systemd 服务。SysV 配置数据可能被原生 systemd 配置覆盖。 
      如果您想列出 systemd 服务,请执行 'systemctl list-unit-files'。
      欲查看对特定 target 启用的服务请执行
      'systemctl list-dependencies [target]'。

sshd            0:关 1:关 2:开 3:开 4:开 5:开 6:关
#配置允许root登录
[root@localhost redhat]# vim /etc/ssh/sshd_config
#在文件中加入下面内容
permitRootlogin yes
#重启sshd
[root@localhost redhat]# systemctl restart sshd
[root@localhost redhat]# systemctl status sshd
● sshd.service - SYSV: OpenSSH server daemon
   Loaded: loaded (/etc/rc.d/init.d/sshd; bad; vendor preset: enabled)
   Active: active (running) since 四 2022-04-07 20:27:03 CST; 25s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 25647 ExecStop=/etc/rc.d/init.d/sshd stop (code=exited, status=0/SUCCESS)
  Process: 25650 ExecStart=/etc/rc.d/init.d/sshd start (code=exited, status=0/SUCCESS)
 Main PID: 25656 (sshd)
   CGroup: /system.slice/sshd.service
           ├─13677 sshd: root@notty
           ├─13679 /usr/libexec/sftp-server
           ├─13785 /usr/libexec/sftp-server
           └─25656 sshd: /usr/sbin/sshd [listener] 0 of 10-100 startups

4月 07 20:27:03 localhost.localdomain systemd[1]: Starting SYSV: OpenSSH server daemon...
4月 07 20:27:03 localhost.localdomain sshd[25656]: Server listening on 0.0.0.0 port 22.
4月 07 20:27:03 localhost.localdomain sshd[25656]: Server listening on :: port 22.
4月 07 20:27:03 localhost.localdomain sshd[25650]: Starting sshd:[  确定  ]
4月 07 20:27:03 localhost.localdomain systemd[1]: Started SYSV: OpenSSH server daemon.
#查看版本
[root@localhost redhat]# ssh -V
OpenSSH_8.9p1, OpenSSL 1.0.2k-fips  26 Jan 2017