How do I shutdown remote Linux or UNIX system from MS-Windows system?
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How do I block port number with iptables under Linux operating systems?
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How do I start / stop or restart Apache web sever via SSH (secure shell) under Linux or UNIX operating systems?
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How do I regenerate OpenSSH sshd server host keys stored in /etc/ssh/ssh_host_* files? Can I safely regenerate ssh host keys using remote ssh session as my existing ssh connections shouldn’t be interrupted on Debian or Ubuntu Linux? How do I regenerate new ssh server keys? How to regenerate new host keys on a Debian or Ubuntu Linux?
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Q. I’ve HP-UX installed on my HP UX UNIX server. But I’m not able to start or restart the OpenSSH ssh server. How do I stop or restart sshd under HP-UX?
A. HP-UX Secure Shell uses Pluggable Authentication Module for password authentication. Server configuration file is located at /opt/ssh/etc/sshd_config.

HP-UX SSHD System Startup and Shutdown script:

/sbin/init.d/secsh {start|stop}

System startup configuration file

/etc/rc.config.d/sshd

Stop HP UX SSH Service

Type the command:
# /sbin/init.d/secsh stop

Start HP UX SSH Service

Type the command:
# /sbin/init.d/secsh start

Both rsh or rlogin prompt for a password. All you need to do is open /etc/hosts.equiv file on host system and add entries for all hosts you would like use without password .

This file list of hosts and users that are granted “trusted” r (rsh/rloging) command access to your system without supplying a password.

$ cat /etc/hosts.equiv

Output:

job1.ha1.nixcraft.com
job2.ha1.nixcraft.com
job3.ha1.nixcraft.com

In above file job1, job2, job3 hosts can connect without a password.

Caution: R (rsh/rlogin) commands are very insecure if possible switch to secure shell (ssh). You can configure ssh so that is does not prompt for a password.