Very slow ssh logins on Fedora 22

I’ve recently set up a Fedora 22 firewall/router at home (more on that later) and I noticed that remote ssh logins were extremely slow. In addition, sudo commands seemed to stall out for the same amount of time (about 25-30 seconds). I’ve done all the basic troubleshooting already: Switch to UseDNS no in /etc/ssh/sshd_config Set GSSAPIAuthentication no in /etc/ssh/sshd_config Tested DNS resolution These lines kept cropping up in my system journal when I tried to access the server using ssh:
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X11 forwarding request failed on channel 0

Forwarding X over ssh is normally fairly straightforward when you have the correct packages installed. I have another post about the errors that appear when you’re missing the xorg-x11-xauth (CentOS, Fedora, RHEL) or xauth (Debian, Ubuntu) packages. Today’s error was a bit different. Each time I accessed a particular Debian server via ssh with X forwarding requested, I saw this: $ ssh -YC myserver.example.com X11 forwarding request failed on channel 0 The xauth package was installed and I found a .
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PXE boot Fedora 19 using a Mikrotik firewall

Outside of the RHCA exams, I haven’t configured a PXE system for my personal needs. A colleague demoed his PXE setup for me and I was hooked. Once I realized how much time I could save when I’m building and tearing down virtual machines, it made complete sense. This post will show you how to configure PXE and tftpd in Mikrotik’s RouterOS to boot and install Fedora 19 (as well as provide rescue environments).
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Changing your ssh server’s port from the default: Is it worth it?

Changing my ssh port from the default port (22) has been one of my standard processes for quite some time when I build new servers or virtual machines. However, I see arguments crop up regularly about it (like this reddit thread or this other one). Before I go any further, let’s settle the “security through obscurity” argument. (This could probably turn into its own post but I’ll be brief for now.
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virt-manager won’t release the mouse when using ssh forwarding from OS X

The latest versions of virt-manager don’t release the mouse pointer when you’re doing X forwarding to a machine running OS X. This can lead to a rather frustrating user experience since your mouse pointer is totally stuck in the window. Although this didn’t affect me with CentOS 6 hosts, Fedora 18 hosts were a problem. There’s a relatively elegant fix from btm.geek that solved it for me. On your Mac, exit X11/Xquartz and create an ~/.
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