openssh升级

centos openssh7.4想升级，下载最新的openssh安装包，
阿里云openssh下载
先按这个流程来：这里

编译openssh时问题：
openssh 编译提示configure: error: OpenSSL library not found.
但是已经安装过openssl，
rpm -qa | grep openssl 有结果
输入openssl version,却找不到命令，

参考这里的第二种方法解决了

原因应该是openssl安装到了其他位置，参考来源：这里
CCFLAGS=“-I/usr/local/openssl/lib/include” LDFLAGS=“-L/usr/local/openssl/lib” ./configure --prefix=/usr --sysconfdir=/etc/ssh --with-pam --with-zlib --with-md5-passwords --with-tcp-wrappers

再执行编译命令，make && make install
cp /data/soft/openssh-9.0p1/contrib/redhat/sshd.init /etc/init.d/sshd

修改sshd_config
是否允许root等

安装完成后卸载telnet

看这里https://blog.youkuaiyun.com/u011529483/article/details/124308340
systemctl start telnet.socket --重启服务器后失效
systemctl start xinetd --重启服务器后失效

查看telnet服务是否启动：netstat -antupl|grep 23

卸载telent

1. 关闭telnet服务
systemctl disable xinetd.service --针对永久生效
systemctl stop xinetd.service
systemctl disable telnet.socket --针对永久生效
systemctl stop telnet.socket
 
2. 执行卸载
rpm -qa | grep telnet
rpm -e --nodeps telnet-server-0.17-66.el7.x86_64
rpm -e --nodeps telnet-0.17-66.el7.x86_64

问题1 权限问题

参考：https://blog.youkuaiyun.com/qq_21782255/article/details/84633623

问题2 公钥发生改变，需要清除本地

WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!
https://blog.youkuaiyun.com/weixin_44462664/article/details/109593652

烟花点7记录：

yum install glibc.i686
yum install glibc-devel
yum install glibc-headers
yum install glibc-common

openssl 升级到3.0.3

#升级 ssl
https://blog.youkuaiyun.com/krioo/article/details/120765525

参考博客：
https://blog.youkuaiyun.com/qq_23934063/article/details/121245871
下载地址：
https://www.openssl.org/source/
https://www.openssl.org/source/openssl-3.0.3.tar.gz

wget https://www.openssl.org/source/openssl-3.0.3.tar.gz --no-check-certificate

# 备份当前Openssl
mv /usr/bin/openssl /usr/bin/openssl_bak
mv /usr/lib64/openssl /usr/lib64/openssl_bak
tar -zxvf openssl-3.0.3.tar.g
cd openssl-3.0.3/
# 编译报错，缺少IPC/Cmd.pm模块
yum install -y perl-CPAN
sudo
install IPC/Cmd.pm
#然后exit
./config shared zlib
make
make install

# 使用新版Openssl
> ln -s /usr/local/bin/openssl /usr/bin/openssl
> ln -s /usr/local/include/openssl/ /usr/include/openssl
> # 使用新版Openssl
> ln -s /usr/local/bin/openssl /usr/bin/openssl
> ln -s /usr/local/include/openssl/ /usr/include/openssl

# 更新动态链接库数据
> echo "/usr/local/lib/" >> /etc/ld.so.conf
> echo "/usr/local/lib64/" >> /etc/ld.so.conf

# 重新加载动态链接库
> ldconfig -v

# 查看安装完成后的最新版本
> openssl version

#解压

解决方法参考：https://blog.youkuaiyun.com/sd4493091/article/details/122220902