How to install openssh from source code in centos 7

Environment: CentOS 7.1.1503 Minimum Installation

Download dependency packages: yum -y install lrzsz zlib-devel perl gcc pam-devel

1. Install openssl and choose the latest released version: openssl-1.1.1g.tar.gz

1) OpenSSL download address: https://www.openssl.org/source/openssl-1.1.1g.tar.gz

2) Uninstall the system pre-installed openssl, this step can be omitted

rpm -qa | grep openssl | grep -v lib

yum -y remove openssl-1.0.1e-42.el7.x86_64

3) Installation steps:

tar -zxvfopenssl-1.1.1g.tar.gz

cdcd openssl-1.1.1g

./config --prefix=/usr/local/openssl --openssldir=/usr/local/openssl -Wl,-rpath,/usr/local/openssl/lib shared

make && make install

4) Create a soft link

ln -s /usr/local/openssl/bin/openssl /usr/bin/openssl

ln -s /usr/local/openssl/include/openssl /usr/include/openssl

5) Update system configuration

echo "/usr/local/openssl/lib" >> /etc/ld.so.conf

/sbin/ldconfig

6) Check the version

openssl version

2. Install openssh, choose the latest released version: openssh-8.3p1.tar.gz

1) OpenSSH download address: https://openbsd.hk/pub/OpenBSD/OpenSSH/portable/openssh-8.3p1.tar.gz

2) Back up the system's openssh configuration file

cp -r /etc/sysconfig/sshd /etc/sysconfig/sshd.bak

cp -r /sys/fs/cgroup/systemd/system.slice/sshd.service /sys/fs/cgroup/systemd/system.slice/sshd.service.bak

cp -r /usr/lib/systemd/system/sshd.service /usr/lib/systemd/system/sshd.service.bak

cp -r /usr/lib/systemd/system/sshd.socket /usr/lib/systemd/system/sshd.socket.bak

cp -r /usr/lib/systemd/system/[email protected] /usr/lib/systemd/system/[email protected]

cp -r /usr/lib/systemd/system/sshd-keygen.service /usr/lib/systemd/system/sshd-keygen.service.bak

3) Uninstall the system pre-installed openssh, this step can be omitted

rpm -qa | grep openssh

yum -y remove openssh-server-6.6.1p1-11.el7.x86_64 openssh-clients-6.6.1p1-11.el7.x86_64 openssh-6.6.1p1-11.el7.x86_64

4) Back up the openssh configuration file. This step can be omitted.

cp -r /etc/ssh /etc/ssh.bak

rm -rf /etc/ssh #This step is very important and must be done

5) Installation steps

tar -zxvf openssh-8.3p1.tar.gz

cd openssh-8.3p1

./configure --prefix=/usr/local/openssh --sysconfdir=/etc/ssh --with-openssl-includes=/usr/local/openssl/include --with-ssl-dir=/usr/local/openssl --with-zlib --with-md5-passwords --with-pam --with-ssl-engine

make && make install

6) Create a soft link

ln -s /usr/local/openssh/sbin/sshd /sbin/sshd

ln -s /usr/local/openssh/bin/ssh /usr/bin/ssh

ln -s /usr/local/openssh/bin/ssh-add /usr/bin/ssh-add

ln -s /usr/local/openssh/bin/ssh-keygen /usr/bin/ssh-keygen

ln -s /usr/local/openssh/bin/ssh-keyscan /usr/bin/ssh-keyscan

7) Restore the backed-up configuration file

mv /etc/sysconfig/sshd.bak /etc/sysconfig/sshd

mv /sys/fs/cgroup/systemd/system.slice/sshd.service.bak /sys/fs/cgroup/systemd/system.slice/sshd.service

mv /usr/lib/systemd/system/sshd.service.bak /usr/lib/systemd/system/sshd.service

mv /usr/lib/systemd/system/sshd.socket.bak /usr/lib/systemd/system/sshd.socket

mv /usr/lib/systemd/system/[email protected] /usr/lib/systemd/system/[email protected]

mv /usr/lib/systemd/system/sshd-keygen.service.bak /usr/lib/systemd/system/sshd-keygen.service

8) Check openssh version

ssh -V

9) Modify the openssh configuration file to allow root login

vi /etc/ssh/sshd_config

Change #PermitRootLogin prohibit-password to PermitRootLogin yes

10) Set the sshd service to start at boot

chkconfig sshd on

11) Restart the sshd service

systemctl restart sshd && systemctl restart sshd && systemctl restart sshd && systemctl restart sshd &

At this point, the openssh service installation is complete. If you are worried, you can reboot the machine

ps: Let's see how to solve the problem of not generating dynamic link library .so when compiling and installing openssl under Linux

The config command provided by the official website does not generate .so by default. The solution is to add the parameter shared when executing ./config, for example:

./config --prefix=/usr/local/ssl --openssldir=/usr/local/ssl -Wl,-rpath,/usr/local/ssl/lib shared

Then make && make install

Summarize

This is the end of this article about how to install openssh from centos 7 source code. For more information about how to install openssh from centos 7 source code, please search 123WORDPRESS.COM's previous articles or continue to browse the following related articles. I hope you will support 123WORDPRESS.COM in the future!