I have installed this on Centos 5.5. The default search engine of mediawiki sucks. Sphinx is a search plugin which uses indexes. It far better than the default one. also better than Semantic Mediawiki plugin.

Visit the page : Mediawiki (Installation instructions)

Note : It not for OS configuration of HBA

#!/bin/ksh
##
##
## Notes:       Linux HBA Checker.  Script to verifying if there is physical conectivity on the HBA cards
##              This does not Check OS configuration
##

OS=`uname -s`

function port_speed {
case $LPFCSPEED_NUM in
0)  LPFCSPEED=”auto select” ;;
1) LPFCSPEED=”1Gb/s” ;;
2) LPFCSPEED=”2Gb/s” ;;
3) LPFCSPEED=”4Gb/s” ;;
4) LPFCSPEED=”8Gb/s” ;;
esac
}

function check_hba {

if [ `/sbin/lspci | grep -i emulex | wc -l` -lt 1 ]
then
echo “No Emulex cards installed”
exit 21
fi

if [ -a /sys/class/scsi_host/host0 ]
then
for hba_dir in `ls -d /sys/class/scsi_host/host*`
do
LPFCNO=`echo ${hba_dir} | awk -F”host/host” ‘{print $2}’`
FIRMWAREREV=`cat ${hba_dir}/fwrev | awk ‘{print $1}’`
LPFCSPEED_NUM=`cat ${hba_dir}/lpfc_link_speed`
port_speed
LPFCSTATE=`cat ${hba_dir}/state | grep Link`
LPWWN=`cat ${hba_dir}/lpfc_symbolic_name | awk -F”-” ‘{print $2}’`

if [ "${LPFCSTATE}" = "Link Up - Ready:" ]
then
pr_pass “lpfc${LPFCNO} ${LPFCSTATE}”
fi

echo “## lpfc${LPFCNO} ##”
echo “Frimware rev =     ${FIRMWAREREV}”
echo “Link_Speed   =     ${LPFCSPEED}”
echo “Link status  =     ${LPFCSTATE}”
echo “WWN          =     ${LPWWN}”
echo ” “
done
exit 0
fi

}

check_hba

• First designate a disk device to which to dump memory. The dump device may be any of the following:
  • a full disk device (e.g. /dev/sda)
  • a partition of a disk device (e.g. /dev/sda4)

* The size of dump device should be large enough to save the whole dump. (With compression and/or the partial dump feature, this can be smaller). The dump size to be written consists of the size of whole physical memory plus a header field. To determine the exact size required, add the following entries to /etc/modprobe.conf or /etc/modules.con (RHEL 3)

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click here to get to the script.

2. Find Files Using Name and Ignoring Case
# find -iname “MyCProgram.c”

3. Limit Search To Specific Directory Level Using mindepth and maxdepth
# find / -name passwd
# find -maxdepth 2 -name passwd
# find / -maxdepth 3 -name passwd
# find -mindepth 3 -maxdepth 5 -name passwd

4. Executing Commands on the Files Found by the Find Command
# find -iname “MyCProgram.c” -exec md5sum {} \;

5. Inverting the match.
# find -maxdepth 1 -not -iname “MyCProgram.c”

6. Finding Files by its inode Number.
find command renames a file using the inode number.
# find -inum 16187430 -exec mv {} new-test-file-name \;
Use the inode number to remove the file that had special character in it as shown below
# find -inum 804180 -exec rm {} \;

7. Find file based on the File-Permissions
# find . -perm -g=r -type f -exec ls -l {} \;
# find . -perm g=r -type f -exec ls -l {} \;
# find . -perm 040 -type f -exec ls -l {} \;

8. Find all empty files (zero byte file) in your home directory and it’s subdirectory
# find ~ -empty
# find . -maxdepth 1 -empty
# find . -maxdepth 1 -empty -not -name “.*”

9. Finding the Top 5 Big Files
# find . -type f -exec ls -s {} \; | sort -n -r | head -5

10. Finding the Top 5 Small Files
# find . -type f -exec ls -s {} \; | sort -n | head -5
# find . -not -empty -type f -exec ls -s {} \; | sort -n | head -5

11. Find Files Based on file-type using option -type

Find only the socket files.
# find . -type s

Find all directories
# find . -type d

Find only the normal files
# find . -type f

Find all the hidden files
# find . -type f -name “.*”

Find all the hidden directories
# find -type d -name “.*”

12. Find files by comparing with the modification time of other file.

Show files which are modified after the specified file. The following find command displays all the files that are created/modified after new_file
# find -newer new_file

13. Find Files by Size
Find files bigger than the given size

# find ~ -size +100M

Find files smaller than the given size

# find ~ -size -100M

Find files that matches the exact given size

# find ~ -size 100M

Note: – means less than the give size, + means more than the given size, and no symbol means exact given size.
14. Create Alias for Frequent Find Operations

If you find some thing as pretty useful, then you can make it as an alias. And execute it whenever you want.

Remove the files named a.out frequently.

# alias rmao=”find . -iname a.out -exec rm {} \;”
# rmao

Remove the core files generated by c program.

# alias rmc=”find . -iname core -exec rm {} \;”
# rmc

15. Remove big archive files using find command

The following command removes *.zip files that are over 100M.

# find / -type f -name *.zip -size +100M -exec rm -i {} \;”

Remove all *.tar file that are over 100M using the alias rm100m (Remove 100M). Use the similar concepts and create alias like rm1g, rm2g, rm5g to remove file size greater than 1G, 2G and 5G respectively.

# alias rm100m=”find / -type f -name *.tar -size +100M -exec rm -i {} \;”
# alias rm1g=”find / -type f -name *.tar -size +1G -exec rm -i {} \;”
# alias rm2g=”find / -type f -name *.tar -size +2G -exec rm -i {} \;”
# alias rm5g=”find / -type f -name *.tar -size +5G -exec rm -i {} \;”

# rm100m
# rm1g
# rm2g
# rm5g

print “try connect\n”;
use IO::Socket;
$remote = IO::Socket::INET->new(
Proto => “udp”,
PeerAddr => “ipaddr”,
PeerPort => “port”,
)
or die “cannot connect to daytime port at localhost”;

print “sending request\n”;
print “GET / HTTP/1.1\nHost: xmlrpc.rhn.redhat.com\n\n”;

print “waiting for response\n”;

while ( ) { print }

#### save this as filename.pl and run

To free pagecache:

echo 1 > /proc/sys/vm/drop_caches

To free dentries and inodes:

echo 2 > /proc/sys/vm/drop_caches

To free pagecache, dentries and inodes:

echo 3 > /proc/sys/vm/drop_caches

1. List All Ports (both listening and non listening ports)

List all ports using netstat -a

List all tcp ports using netstat -at

List all udp ports using netstat -au

2. List Sockets which are in Listening State

List only listening ports using netstat -l

List only listening TCP Ports using netstat -lt

List only listening UDP Ports using netstat -lu

List only the listening UNIX Ports using netstat -lx

3. Show the statistics for each protocol

Show statistics for all ports using netstat -s

Show statistics for TCP (or) UDP ports using netstat -st (or) -su

4. Display PID and program names in netstat output using netstat -p

netstat -p option can be combined with any other netstat option. This will add the “PID/Program Name” to the netstat output. This is very useful while debugging to identify which program is running on a particular port

5. Don’t resolve host, port and user name in netstat output

When you don’t want the name of the host, port or user to be displayed, use netstat -n option. This will display in numbers, instead of resolving the host name, port name, user name.

This also speeds up the output, as netstat is not performing any look-up.

# netstat -an

If you don’t want only any one of those three items ( ports, or hosts, or users ) to be resolved, use following commands.

# netsat -a –numeric-ports

# netsat -a –numeric-hosts

# netsat -a –numeric-users

6. Print netstat information continuously

netstat will print information continuously every few seconds.

# netstat -c

7. Find the non supportive Address families in your system

netstat –verbose

8. Display the kernel routing information using netstat -r

# netstat -r

9. Find out on which port a program is running

# netstat -ap | grep ssh

10. Show the list of network interfaces

# netstat -i

Display extended information on the interfaces (similar to ifconfig) using netstat -ie:

# netstat -ie

Stop mysql

mysqld_safe –skip-grant-tables –user=mysql &

[root@server ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1 to server version: 4.0.20-standard

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the buffer.

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql> UPDATE mysql.user SET Password = PASSWORD(”) WHERE user = ‘root’;
Query OK, 3 rows affected (0.00 sec)
Rows matched: 3  Changed: 3  Warnings: 0

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql> QUIT
Bye
[root@server ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2 to server version: 4.0.20-standard

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the buffer.

mysql> quit
Bye
[root@server ~]# /etc/init.d/mysql stop
Killing mysqld with pid 8433
Wait for mysqld to exit.. done
[root@server ~]# /etc/init.d/mysql start
[root@server ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1 to server version: 4.0.20-standard

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the buffer.

mysql> show databases;
+———-+
| Database |
+———-+
| mysql    |
+———-+
1 row in set (0.00 sec)

mysql>

In this tutorial I will describe how to set up a highly available NFS server that can be used as storage solution for other high-availability services like, for example, a cluster of web servers that are being loadbalanced. If you have a web server cluster with two or more nodes that serve the same web site(s), than these nodes must access the same pool of data so that every node serves the same data, no matter if the loadbalancer directs the user to node 1 or node n. This can be achieved with an NFS share on an NFS server that all web server nodes (the NFS clients) can access.

As we do not want the NFS server to become another “Single Point of Failure”, we have to make it highly available. In fact, in this tutorial I will create two NFS servers that mirror their data to each other in realtime using DRBD and that monitor each other using heartbeat, and if one NFS server fails, the other takes over silently. To the outside (e.g. the web server nodes) these two NFS servers will appear as a single NFS server.

In this setup I will use Debian Sarge (3.1) for the two NFS servers as well as for the NFS client (which represents a node of the web server cluster).

I want to say first that this is not the only way of setting up such a system. There are many ways of achieving this goal but this is the way I take. I do not issue any guarantee that this will work for you!

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