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This doc contains the things I've found I need to update to get my linux2 server working.
Changing default serial port protections
create a file, such as <code>99-local.rules</code> in the following directory: <code>/etc/udev/rules.d/</code> with the following info:
<pre>
- Give world read/write access to ttyS* and ttyUSB* serial devices
KERNEL=="tty[A-Z]*", GROUP="uucp", MODE="0666" </pre>
Ubuntu dual monitors
Run <code>nvidia-settings</code>. Now we may need to modify the Xconf file, if so see the following:
- Open nvidia-settings by searching for nvidia in the Dash, or run the command gksudo nvidia-settings in the Terminal. Note not to press the apply button.
- Under 'Xserver Display Configuration' select TwinView and configure the settings for the monitors to your liking.
- Click 'Save to X Configuration File' and an error message should appear. Click OK.
- In the next dialog box click the button to 'Show Preview'.
- Leave the preview window open and open a Terminal. Run the following commands in the Terminal to back up your xorg.conf file and open the original file in a test editor. If something goes wrong, just revert to your backed up xorg.conf.
- sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.bak
- gksudo gedit /etc/X11/xorg.conf`
- Copy the text from the nvidia-settings preview window into the xorg.conf file. Save the xorg.conf file and close gedit. Click 'Cancel' to close the nvidia-settings preview window. Then click 'Quit' to exit completely out of nvidia-settings without applying or saving any data.
- Restart your computer. If all went well, the two monitors should work together.
Note: As of ubuntu 12.04 you don't appear to need to copy the xorg.conf files around. Just clicking save is all it takes.
Rebuilding Raid
Rebuilding a raid system?
Detail from mdadm of good working file system prior to zeroing the superblock.
<pre> sudo mdadm --detail /dev/md4 /dev/md4:
Version : 0.90 Creation Time : Sat Mar 19 08:02:27 2011 Raid Level : raid6 Array Size : 160649856 (153.21 GiB 164.51 GB) Used Dev Size : 80324928 (76.60 GiB 82.25 GB) Raid Devices : 4 Total Devices : 4
Preferred Minor : 4
Persistence : Superblock is persistent
Update Time : Sun Jun 3 21:06:27 2012 State : clean Active Devices : 4
Working Devices : 4
Failed Devices : 0 Spare Devices : 0
Layout : left-symmetric Chunk Size : 64K
UUID : b60f9401:efa1275e:6caba8f0:d8b2a7d7 Events : 0.457
Number Major Minor RaidDevice State 0 8 66 0 active sync /dev/sde2 1 8 82 1 active sync /dev/sdf2 2 8 98 2 active sync /dev/sdg2 3 8 50 3 active sync /dev/sdd2
</pre>
Note, the drive order is very important. Also, remove the ARRAY entry from /etc/mdadm/mdadm.conf for the drive.
<pre> sudo mdadm --stop /dev/md6 sudo mdadm --zero-superblock /dev/sd[defg]2 sudo mdadm --create /dev/md6 --metadata=1.0 --chunk=64 --level=6 --raid-devices=4 /dev/sde2 /dev/sdf2 /dev/sdg2 /dev/sdd2 </pre>
Ok, now we need to get the blkid from the md filesystem and add an entry into the mdadm.conf file which matches.
<pre> sudo blkid /dev/md6 # edit mdadm.conf file and add entry "ARRAY /dev/md6 UUID=dad67a5c:0907045c:7eb49ca0:d0f6f000" sudo mdadm --assemble /dev/md6 --update=resync sudo mdadm --detail /dev/md6 sudo blkid /dev/md6 sudo mount -t ext3 /dev/md6 /mnt/temp
watch -n 1 cat /proc/mdstat </pre>
or... ???
<pre> sudo mdadm --stop /dev/md6 sudo mdadm --zero-superblock /dev/sd[defg]2 sudo mdadm --create /dev/md6 --metadata=0.9 --chunk=64 --level=6 --raid-devices=4 /dev/sde2 /dev/sdf2 /dev/sdg2 /dev/sdd2 sudo mdadm --assemble /dev/md6 --update=resync sudo mdadm --detail /dev/md6 sudo blkid /dev/md6 sudo mount -t ext3 /dev/md6 /mnt/temp </pre>
If this is a new raid drive, make the filesystem then mount
<pre> sudo mkfs /dev/md6 sudo mount /dev/md6 /mnt/temp </pre>
Fixing mail permission errors on linux2
Do the following: <pre> sudo touch /var/mail/$USER sudo chown $USER:mail /var/mail/$USER sudo chmod o-r /var/mail/$USER sudo chmod g+rw /var/mail/$USER </pre>
Updates to tzo configuration
After installing tzo I needed to update the <code>tzod</code> script in <code>/etc/init.d</code>. I updated the following script segment to look like this (basically just added the lines with <code>/lib/lsb...</code>: <pre> if [ -f /etc/rc.d/init.d/functions ]; then
. /etc/rc.d/init.d/functions
elif [ -f /etc/init.d/functions ] ; then
. /etc/init.d/functions
elif [ -f /lib/lsb/init-functions ] ; then
. /lib/lsb/init-functions
else </pre>
Next I added a soft link in the <code>/etc/rc.5.d/</code> directory: <pre> sudo ln -s ../init.d/tzod S99tzod </pre>
Trick for port forwarding
This lets me access the CUPS system on the linux2 server from my linux laptop. Issue this command on the laptop, insert the appropriate passwords...
<pre> ssh -L 6310:localhost:631 root@remote_ip_address </pre>
Now access the cups system via the browser on the laptop by going to <code>localhost:6310</code>.
Making movies from jpg files
This seems to work...
<pre> mencoder -ovc copy -mf w=320:h=240:fps=12:type=jpg "mf://*.jpg" -o output.avi mencoder -ovc copy -mf w=320:h=240:fps=12:type=jpg "mf://@list.txt" -o output.avi </pre>
Raspberry pi serial port
http://www.raspberrypi.org/forums/viewtopic.php?&t=27035
Backing up the server
Run the following command on the desktop which has the backup disk mounted. This will backup /home to the backup drive, and this command should be repeated for each filesystem on linux server. rsync is now enabled on the msgsb.com server.
rsync -avzH linux2:/home2 /media/mhamilton/Seagate\ Backup\ Plus\ Drive/home2/
Also this can be run on the pi at the condo. Login to the condo pi and run the following commands:
ssh pi@h-condo.dyndns.org rsync -avzh mhamilton@msgsb.com:/home3 /backup-msgsb/home3
To setup ssh to not query for passwords, from the pi:
ssh-keygen ssh-copy-id -i ~/.ssh/id_rsa.pub mhamilton@msgsb.com
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