Fixing X11 Forwarding Over SSH and with Sudo

X11 forwarding over SSH not working? Not setting $DISPLAY correctly in your shell? Having problems with X11 and sudo? Yeah, me too. Total pain in the duff. Here’s what I do to fix it. I’m thinking about Linux when I write stuff like this but a lot of this has worked on AIX and Solaris, too. Make sure your SSH client supports X11 Forwarding and that it’s turned on. I use SecureCRT but I know it works in PuTTY as well. Once you turn it on in your client & save the settings you will need to reconnect, the forwarding is established with the connection. Ensure xauth and xterm are installed. You need xauth for this to work, and xterm …

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How to Disable Windows IPv6 Temporary Addresses

The default Microsoft Windows IPv6 implementation has privacy extensions enabled, where IPv6 temporary addresses areĀ used for client activities. The idea is that IPv6 has so many addresses available to it that we can create extra ones to help mask our activities. In practice these temporary addresses are largely pointless, and are very unhelpful if firewalls and ACLs are configured to allow access from a specific static address. By themselves, IP addresses aren’t a good way to authenticate people but they often form another layer of defense. This is especially important for IT infrastructure where there often aren’t (or can’t be) sophisticated authentication mechanisms. Paste these commands into an administrator-level PowerShell or Command Prompt and then restart your PC: netsh interface …

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How To Disable Teredo IPv6 Tunneling in Microsoft Windows

Greg Ferro’s post about how Microsoft Teredo is a suboptimal networking solution made me think it’s time to update my old post on how to disable Teredo in Windows 7 and in Windows 8. For the record, I agree — I’ve had serious problems with it conflicting with my native IPv6 connectivity. 1. Open a command prompt with administrator privileges (Start->Accessories->right click on Command Prompt, choose Run as Administrator): 2. Issue the command: netsh interface teredo set state disabled 3. You may need to reboot, depending on your version of Windows. If you wish to re-enable Teredo at some point you can issue the command: netsh interface teredo set state type=default