Linux: grubby; useful command to manipulate kernel configuration from command line 
To get the inforamtion which is the default kernel use this command:

# grubby --default-kernel

To update the default kernel with a parameter you can do this:
grubby --update-kernel="$( grubby --default-kernel )" --args="crashkernel=512M@16M"

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Linux RHEL: reset HP server remotely with ilo (fence_ilo) 
To use the script below to remotely reset HP server vith ILO, you have to create the fence user in ILO and assign permission to remotely reset the server.


# name: fence_server
# desc: the script resets the server remotely via iLO2 (HP servers)
# if the server is not pingable. the script tries to ping
# the server several times before issuing reset.
# req: package cman must be installed (includes /sbin/fence_ilo)

SCRIPT_NAME=`basename $0`


# server to ping

# ilo to server

# retries before kill
WAIT_ROUNDS=3 # 3 retries
WAIT_TIME=600 # 10 minutes

# try to ping the server
for waits in $( seq 1 $WAIT_ROUNDS )
ping -q -c 3 $SERVERNAME > /dev/null
[ $? -eq 0 ] && exit
sleep $WAIT_TIME

# server is not reachable via ICMP, perform reset
echo "$SCRIPT_NAME is trying to reset the server $SERVERNAME via $ILO_HOSTNAME" >> $TMP_FILE

# do the fence
/sbin/fence_ilo -a $ILO_HOSTNAME -l $ILO_ACCOUNT -p $ILO_PASSWD -v >> $TMP_FILE

# log the output to syslog
while read line
done < $TMP_FILE


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OpenVPN clietn setup and tun/tap OpenVPN routing explanation ... ients.html ... PN/Routing

ccd/client file must contain:

where the is the LAN beyond the client (ie.router)

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Welcome to the Church of the Flying Spaghetti Monster.

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VmWare: check virtualu a vseho dalsiho na esxi  
Nagios Plugin:

This is a Nagios plugin to monitor the hardware of mainly ESXi servers. It can as well be used for ESX servers but there are better plugins in combination with OpenManage or InsightAgents available. The plugin is written in python, so you need to have python installed. ... rdware.php ...

Procedures to install ASM-CIMProvider and RemoteArcconf for VMware ESXi 4.1 ... 3_2011.pdf

Hardware Health Monitoring via CIM, part 5 ... art-5.html

Adaptec RAID Check by Anchor Systems ... ms/details

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Staff Paper 
Staff Paper

Diminished Scale ... /minor.pdf

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Linux: create ramdisk 
To create ramdisk to process the data within

# mkdir /var/ramdisk
# mount -t tmpfs none /var/ramdisk -o size=12G

tmpfs is a common name for a temporary file storage facility on many Unix-like operating systems. It is intended to appear as a mounted file system, but stored in volatile memory instead of a persistent storage device. A similar construction is a RAM disk, which appears as a virtual disk drive and hosts a disk file system.

Everything stored in tmpfs is temporary in the sense that no files will be created on the hard drive; however, swap space is used as backing store in case of low memory situations. On reboot, everything in tmpfs will be lost.

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Left-hand Comping on Autumn Leaves

How to Play an Andy Laverne Pedal Point ... -306972909

How to Play Piano: Practicing C9's ... 9s-2459423

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CentOS/RHEL Watchdog install 
Watchdog is a software which resets the machine if the machine is in some of the crash defunct state but the kernel lives somehow. The watchdog can be configured to check if the system is responsive via writting to the /dev/watchdog and some other subsequent check could be set up as well.

Watchdog opens /dev/watchdog and keeps writing to it often enough to keep the kernel from resetting, at least once per minute. Each write delays the reboot time another minute. After a minute of inactivity the watchdog hardware will cause the reset. In the case of the software watchdog the ability to reboot will depend on the state of the machines and interrupts.

# yum install watchdog

watchdog consists of the watchdog daemon and a kernel module softdog.


If the watchdog complains the device through which the process comunicates with the module /dev/watchdog is missing you have to create the device

# mknod /dev/watchdog c 10 130

in basic configuration the only change sufficient in /etc/watchdog.conf is to uncomment

file = /var/log/messages
watchdog-device = /dev/watchdog

I do recommend to check the watchdog documentation bundled in /usr/share/doc/watchdog

# rpm -ql watchdog

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