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Openbsd

Linux / UNIX: Kill Unresponsive SSH Session

Sometime my ssh session just stops working because of the internet connection problem. I tried pressing CTRL+Z and CTRL+C to terminate session, but failed to work. How do I properly kill a hung SSH session without killing my local terminal or using kill command?
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Sysadmin because even developers need heroes!!!

Linux / UNIX: Speed up SSH X11 Forwarding

I‘ve an CentOS based server and Ubuntu based desktop pc. I’m connecting to my CentOS using ssh X11 forwarding feature. However, speed over the Internet is pretty slow for certain apps such as VMWare console. How do I speed up OpenSSH X11 forwarding using Linux / UNIX desktop system?
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OpenBSD Command: See PCI Device Information

How do I see PCI devices information under OpenBSD operating systems using command line interfaces?
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Rsync Change SSH Port Number While Making Backups

How do I change my rsync command port number while making backup to remote server at backup1.example.com port 10253 (my ssh server runs on tcp port # 10253)? How do I change port number while using rsync command?
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Linux KVM: OpenBSD Guest Hangs At Starting tty Flags

OpenBSD version 4.5 and above made changes in kernel which prevents booting OpenBSD using KVM technology. OpenBSD 4.4 runs with mbbios enabled. However, due to some sort of bug in KVM it does not boot and hangs while displaying a message which read as “Starting tty flags”. The workaround is to disable mpbios. This may or may not happen with your installation, but if it hanged, use the following procedure.
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KVM virt-install: Install OpenBSD As Guest Operating System

OpenBSD is a UNIX like system based on Berkeley Software Distribution (BSD). It was forked form NetBSD and created by Theo de Raadt in 1995. OpenBSD is famous for quality code and documentation without compromising position on software licensing. OpenBSD is also well know for focus on security features such as Memory protection, cryptography, randomization and much more in default base installation.
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OpenBSD: Setup a Serial Console

How do I enable console redirection under OpenBSD so that I can see my remote server boot information and any diagnostic information that is normally printed to the screen? I’ve already enabled serial ports in my server BIOS and wired them up. How do I configure and access OpenBSD UNIX x86/amd64 server over serial console?
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OpenBSD: Static Routing Configuration

I know how to setup static routing under Linux and FreeBSD operating systems. But, how do you setup static routing under OpenBSD operating systems?
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Force SSH Client To Use Given Private Key ( identity file )

Recently, my desktop hard disk crashed. So I reinstalled Linux and created a new set of private RSA keys for authentication. However, two of my remote UNIX servers still uses old DSA keys. I do not remember root password for those servers. I do have backup of private and public DSA keys and currently stored in /backup/home/user/.ssh/id_dsa and /backup/home/user/.ssh/id_dsa.pub. How do I force my ssh clients to use identity file /backup/home/user/.ssh/id_dsa to get back to my remote UNIX servers?
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Install / Append SSH Key In A Remote Linux / UNIX Servers Authorized_keys

How do I install my SSH public key ~/.ssh/id_rsa.pub onto a remote Linux and UNIX server automatically from Linux workstation or Apple OS X laptop without using scp and/or copy & paste method?
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