It is still raining. Using the time to do some sysadmin work and training puppet.
Found a nice cheat sheet for mdadm.
mdadm --create --verbose /dev/md0 --level=raid10 --raid-devices=4 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1
mdadm --create --verbose /dev/md1 --level=raid10 --raid-devices=4 /dev/sdf1 /dev/sdg1 /dev/sdh1 /dev/sdi1 mdadm --examine --scan --config=mdadm.conf >> /etc/mdadm/mdadm.conf
vgcreate raid10_big /dev/md0
vgcreate raid10_small /dev/md1
This is how I can create a backup from a running xen instance with the help of a lvm snapshot:
# Create the snapshot volume of 1GB size
# named domS2U01_bak of volume /dev/RAID/domS2U01_root
lvcreate -L1G -s -n domS2U01_bak /dev/RAID/domS2U01_root
# Mount the snapshot volume
mount /dev/RAID/domS2U01_bak /mnt/debian
# change to mounted volume
# make backup
tar zcpvf /mnt/backup/domS2U01_20121110.tgz .
# remove the snapshot
This tutorial from the LVM HOWTO helped me.
If it ever happens that a harddrive fails in a software RAID this is a short note how to replace it.
# check status
# mark drive / partition as failed
mdadm --manage /dev/md0 --fail /dev/sdb1
# remove drive / partition from raid
mdadm --manage /dev/md0 --remove /dev/sdb1
Now replace the harddrive with a new one.
Format and partition the new drive.
It's partition type should be fd. Make sure that the new partition or drive has the same size or bigger as the old driver or partition.
# check the smart status of the new drive
smartctl -t long /dev/sdb
# wait until it is finished and verify smart status is ok
smartctl -l selftest /dev/sdb
# add the new driver / partition to the degraded raid
mdadm --manage /dev/md0 --add /dev/sdb1
I found this tutorial
on howtoforge helpful.
Today was the training day of Unity3D's Unite 2012
To avoid getting segmentation faults on a synology device you have to use -d sat and the full path to the command:
(mine is a DS411s)
/usr/syno/bin/smartctl -d sat -l selftest /dev/sdd
You might have notices that our game "frank the fish" is also available on google play.
You can play it on modern Android phones.
Frank the fish is a game designed for kids. But it makes fun for grown ups as well.
Surprisingly porting to Android took not so much time.
The only thing we had and wanted to do is to support the hardware keyboard of xperia play devices.
Once you open the hardware keyboard the onscreen HUD disappears and you can enjoy the scene.
Have fun playing it.
PS: don't forget to check out our youtube and facebook page.
Just did again some graphing with rrd.
Thinking (googling) some metrics to graph I found some interesting articles:
- some nice rrd examples: link
- List of Cacti Scripts and Templates: link (I did not try them out yet!)
- 20 Linux System Monitoring Tools Every SysAdmin Should Know: link
- article about graphing spend cpu ticks: link
- opennms graph gallery: link
- tool to create color gradient steps: link (mentioned in the link above)
- pmacct could be used to get protocols out of network traffic: link (will try it, once I have more time)
And here are some pics:
(as this machine is idleing it graphs only between 0 and 5 %)
Btw: am using catcti to graph and some custom code to push metrics to cacti. Will post about it, once it is on github.
...to prepare some photos to play with Photomatix Pro.
it's a bit unsharp without a RC - out of battery exception :-)
Arg, ok, back with debian for my servers and new hardware.
With debian I got a more recent kernel for xen (someone forward ported xen to the current debian stable kernel), but an older xen hypervisor.
However I need an even newer igb network driver (where gentoo had backported them).
This line only builds the xen flavour:
fakeroot make -f debian/rules.gen binary-arch_amd64_xen
Location of the full howto.
Building only the kernel module:
apt-get install linux-headers-2.6.26-2-xen-amd64
/usr/src/igb-2.3.4/src && make && make install