Monday, June 29, 2009

Remote X11 via ssh and Xnest

One of the coolest things I've found recently is Xnest. I can "ssh -X" into a UNIX box and do "Xnest :1 -query 127.0.0.1" to get the XDMCP general login window. Slick. Apple-Click gives me a right click from my OSX box.

Removing VESA mode after ubuntu install

To install ubuntu on a machine with a "Intel Corporation 82845G/GL[Brookdale-G]/GE Chipset Integrated Graphics Device (rev 03)" chipset, I had to use the "VESA" install mode. Once installed it wouldn't use any other so I had to remove the 'Driver "vesa"' line from /etc/X11/xorg.conf for ubuntu to use the higher screen resolutions available. I still haven't found out how to make compiz work under ubuntu; it did under RedHat...

ssh tunnel to exim4

In order for exim4 to pay attention to a client connected via an ssh tunnel, one has to add the IP address of the machine to the "dc_relay_nets" line in /etc/exim4/update-exim4.conf.conf.

mutt default colors

Mutt's default color scheme is white on black. To use the terminal's default color scheme, one must have a "color normal default default" line in their .muttrc. Why? No clue. Shouldn't that be the default?

Command-line ubuntu upgrade

I've a bunch of short things I need to catch up on. Here's a few:

sudo apt-get upgrade

To remove an older kernel:
sudo dpkg -l | grep linux-image
sudo dpkg -r linux-image-2.6.xxx

Friday, June 12, 2009

OpenSSH frustrations

I've written before about OpenSSH not working with an OSX box, but the troubles are bigger than that. I've had on-going problems transferring files from either a FC or Ubuntu box to sourceforge. Very strange. Poking around, there were references to DNS being an issue, and sure enough, if I use the IP address of the remote host instead of the host name, the transfers work no problem. What's up with this??? I check both the forward and reverse lookups with no issues. What would cause the stalling behavior? No clue.

It also appears that OpenSSH plays around at the IP level. It really shouldn't, being an application-layer protocol and all. I've used Jsch (http://www.jcraft.com/jsch/) to good effect and we all know Java doesn't play at the IP layer. Indeed, I have been using jsch to tunnel instead of OpenSSH.

Oxymoron: Microsoft Intellitype

Ran into a problem with a Dell Latitude 830 when connected to an external projector: PowerPoint and other programs would zoom to 400% no matter what. When scaled back, they would zoom again. I found one reference to this strange behavior: http://www.experts-exchange.com/OS/Miscellaneous/Q_22099388.html Remove Intellitype and things were good again. It appears it only affects Latitude 800 series, but I can't be sure of that of course.

Sunday, June 7, 2009

exim4 and spamassasin

There seems to be no one easy place to find out how to integrate the two. Here's one.
  1. Get (yum or apt-get) and install exim4-daemon-heavy, spamassassin, and sa-exim. Configure exim4 the way you need it, but use the "split" configuration scheme.
  2. Change the line in /etc/exim4/sa-exim.conf to SAEximRunCond: 1 It says you can comment it out but you can't. That leaves SAEximRunCond undefined which means false.
  3. Make sure /etc/exim4/update-exim4.conf.conf has dc_use_split_config='true'
  4. Edit /etc/exim4/conf.d/main/02_exim4-config_options and uncomment the 'spamd_address' line
  5. sudo update-exim4.conf -v
  6. sudo service exim4 restart