Configure ramdisk for Openfiler

Create a new file under /etc/bootloader.d directory. In this new file, type add_options ramdisk_size=32000. Please note that the unit is in kilobytes. The example below shows the new file is called ramdisk.conf and the content of this file.

[root@abc ~]# cd /etc/bootloader.d
[root@abc bootloader.d]# ls
distro-defaults.conf  plymouth-bootloader.conf  ramdisk.conf  syslinux_bg.png
[root@abc bootloader.d]# more ramdisk.conf
add_options ramdisk_size=32000

After the file is created, type bootman to apply the configuration as shown below

[root@abc ~]#bootman

Restart your machine and you can check whether is it successful by typing cat /proc/cmdline as shown below:

[root@abc ~]# cat /proc/cmdline
mce=dont_decode cciss.cciss_allow_any=1 splash quiet ramdisk_size=32000 ro root=LABEL=/ initrd=/initrd-2.6.32-71.18.1.el6-0.20.smp.gcc4.1.x86_64.img BOOT_IMAGE=/vmlinuz-2.6.32-71.18.1.el6-0.20.smp.gcc4.1.x86_64

Create a filesystem on /dev/ram0 and mount it up and you will have a 32MB ramdisk.

PowerShell to check MSSQL database status

A very simple Powershell script to check database status.

[System.Reflection.Assembly]::LoadWithPartialName('Microsoft.SqlServer.SMO') | out-null
$s = New-Object ('Microsoft.SqlServer.Management.Smo.Server') ServerName
$db = $s.Databases.item("databaseName")
"status: " + $db.status + " isaccessible: " + $db.isaccessible

Example output:
Database status is normal

status: Normal isaccessible: True

This output is created by renaming the log file.

status: RecoveryPending isaccessible: False

For more status description, please refer to this Microsoft site.

Useful Linux Command - mkdir -p

-p (parents) option for mkdir gives you the ability to create a multiple levels deep directory with all the intermediate directories created as well.

Example: When you want to create a directory tree like this /a/b/c/d, where a,b,c,d are all not exist before, you need to create each directory independently like

mkdir /a
mkdir /a/b
mkdir /a/b/c
mkdir /a/b/c/d

if you do mkdir /a/b/c/d, you will encounter "no such file or directory" error.

With -p option, you can create /a/b/c/d with just one single line of command as shown below:

mkdir -p /a/b/c/d

Load Brocade CNA driver for Openfiler

1. Download the rpm package from Brocade website. Choose the "Linux - Other Distributions".
2. Perform the following steps to extract the bna files (Ethernet package) out from the rpm package

rpm2cpio bna_driver_linux-3.0.3.0-0.noarch.rpm > temp-file.cpio
cpio -idumv < temp-file.cpio

3. You should be able to see a usr folder in your working path. Copy all the files inside ./usr/src/bna folder to the /usr/src/.

cp ./usr/src/bna /usr/src/ -R

4. Go to /usr/src/bna and execute make.
5. After that, you should be able to locate a file call bna.ko in the /usr/src/bna directory.
6. Run insmod bna.ko to install the module and then you have your Ethernet driver loaded successfully.

Ubuntu: Running Dynamo Executable: No such file or directory

Symptom:

root@testMachine:~/iometer-2006_07_27.linux.i386-bin/src# ls
dynamo  iomtr_kstat  scripts
root@testMachine:~/iometer-2006_07_27.linux.i386-bin/src# ./dynamo
-bash: ./dynamo: No such file or directory

For this case, you need to make sure you have ia32-libs installed. To check whether the package is installed, run:

root@testMachine:/# dpkg -l ia32-libs
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name           Version        Description
+++-==============-==============-============================================
ii  ia32-libs      20090808ubuntu ia32 shared libraries for use on amd64 and i

if it shows "un", meaning ia32-libs is not installed. If is installed, it will show "ii".

Install ia32-libs by

apt-get install ia32-libs

* Please note that, for simplicity, i using root account to run the above command, you might need to add sudo in front of the above commands if you are not using root account.

dpkg : status database area is locked by another process while trying to install

This will happen if you accidentally kill the apt-get process and dpkg become orphan process. To solve this problem you can either

Reboot your server or do the following:

sudo rm /var/lib/dpkg/lock

sudo dpkg --configure -a

How to change boot order for Ubuntu (>9.10)

1. cat /boot/grub/grub.cfg
see the order of the wanted kernel. Starts from 0.

Example:

...
### BEGIN /etc/grub.d/10_linux ###
menuentry 'Ubuntu, with Linux 2.6.35-30-server' --class ubuntu --class gnu-linux
# this is 0
--class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 71119ab7-e93f-49a9-80f1-efc11398c954
linux /boot/vmlinuz-2.6.35-30-server root=UUID=71119ab7-e93f-49a9-80f1
-efc11398c954 ro quiet
initrd /boot/initrd.img-2.6.35-30-server
}

# this is 1
menuentry 'Ubuntu, with Linux 2.6.35-30-server (recovery mode)' --class ubuntu -
-class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 71119ab7-e93f-49a9-80f1-efc11398c954
echo 'Loading Linux 2.6.35-30-server ...'
linux /boot/vmlinuz-2.6.35-30-server root=UUID=71119ab7-e93f-49a9-80f1
-efc11398c954 ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.35-30-server
}

# this is 2
menuentry 'Ubuntu, with Linux 2.6.32-28-server' --class ubuntu --class gnu-linux
--class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 71119ab7-e93f-49a9-80f1-efc11398c954
linux /boot/vmlinuz-2.6.32-28-server root=UUID=71119ab7-e93f-49a9-80f1
-efc11398c954 ro quiet
initrd /boot/initrd.img-2.6.32-28-server
}

# this is 3
menuentry 'Ubuntu, with Linux 2.6.32-28-server (recovery mode)' --class ubuntu -
-class gnu-linux --class gnu --class os {
recordfail
insmod part_msdos
insmod ext2
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set 71119ab7-e93f-49a9-80f1-efc11398c954
echo 'Loading Linux 2.6.32-28-server ...'
linux /boot/vmlinuz-2.6.32-28-server root=UUID=71119ab7-e93f-49a9-80f1
-efc11398c954 ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.32-28-server
}
### END /etc/grub.d/10_linux ###
...

2. vi /etc/default/grub
change GRUB_DEFAULT=0 value to wanted kernel

Example:

If we want to boot to 'Ubuntu, with Linux 2.6.32-28-server' we should set 2

3. run update-grub to update

4. reboot and check with uname -r to see if correct kernel selected.