Lvm on xen with full steps

In this example,expanding the nagios machine (lvm size)
Use the following steps to expand VM size ( lvm expand)

1) #xm list (showning running VM)
[root@inf1basevm01 ~]# xm list
Name ID Mem(MiB) VCPUs State Time(s)
Domain-0 0 7269 4 r----- 4505.4
ind1basevm01 1 255 1 -b---- 17.3
ind1infra01 2 255 1 -b---- 17.4
nagios 4 256 1 -b---- 0.3

Showing 3 running virtual machines.

2)shut down the running VM (through login or use following command)

#xm shutdown nagios

3) use fdisk to check...

[root@inf1basevm01 ~]# fdisk -l /dev/VmImage/nagios

Disk /dev/VmImage/nagios: 16.1 GB, 16106127360 bytes
255 heads, 63 sectors/track, 1958 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/VmImage/nagios1 * 1 13 104391 83 Linux
/dev/VmImage/nagios2 14 1958 15623212+ 8e Linux LVM

***now Disk size is 16.1GB***

4) Now expand the LVM size.

[root@inf1basevm01 ~]# lvextend /dev/VmImage/nagios -L +2GB
Extending logical volume nagios to 17.00 GB
Logical volume nagios successfully resized

5) Now check again with fdisk.

[root@inf1basevm01 ~]# fdisk -l /dev/VmImage/nagios

Disk /dev/VmImage/nagios: 18.2 GB, 18253611008 bytes
255 heads, 63 sectors/track, 2219 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

*** you able to see 18.2GB (mean 2GB expand)***

6) Now start the VM

#xm create nagios
Using config file "/etc/xen/nagios".
Started domain nagios

7) # xm list
[root@inf1basevm01 ~]# xm list
Name ID Mem(MiB) VCPUs State Time(s)
Domain-0 0 7269 4 r----- 4505.4
ind1basevm01 1 255 1 -b---- 17.3
ind1infra01 2 255 1 -b---- 17.4
nagios 4 256 1 -b---- 0.3

Its show all 3 VM are up now.

---------------------------------------------------------------------------------
Now very important part....
Login as root on nagios machine (VM machine)

Run #fdisk -l and #df -h ( you got the difference)

Now run
#fdisk /dev/xvda (create partition)
according to yours.

use partprobe command or reboot the machine to make online disk.

#partprobe

After that run pvdisplay ( to check current physical volume)

#pvdisplay

Now create physical volume on /path/of/drive like following

# [root@nagios ~]# pvcreate /dev/xvda3
Physical volume "/dev/xvda3" successfully created
[root@nagios ~]# vgdisplay

Now run vg display for check volume group

#vgdisplay

Now extend you VG

#[root@nagios ~]# vgextend VolGroup00 /dev/xvda3
Volume group "VolGroup00" successfully extended

**VolGroup00 is VG name**

#vgdisplay

Now extend you LVM

#lvdisplay

#[root@nagios ~]# lvextend /dev/VolGroup00/root -L +3.90GB
Rounding up size to full physical extent 3.91 GB
Extending logical volume root to 17.78 GB
Logical volume root successfully resized


Now run following command very carefully

#[root@nagios ~]# resize2fs /dev/VolGroup00/root 17G
resize2fs 1.39 (29-May-2006)
Filesystem at /dev/VolGroup00/root is mounted on /; on-line resizing required
Performing an on-line resize of /dev/VolGroup00/root to 4456448 (4k) blocks.
The filesystem on /dev/VolGroup00/root is now 4456448 blocks long.



***The resize2fs program will resize ext2 or ext3 file systems. It can be used to enlarge or shrink an unmounted file system located on device. If the filesystem is mounted, it can be used to expand the size of the mounted filesystem, assuming the kernel supports on-line resizing. (As of this writing, the Linux 2.6 kernel supports on-line resize for filesystems mounted using ext3 only.)*****

Now Run following command to check space.

[root@nagios ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-root
18G 1.1G 16G 7% /
/dev/xvda1 99M 21M 74M 22% /boot
tmpfs 129M 0 129M 0% /dev/shm


That's End of the story.........Hope this work for you.... Enjoy and have a nice day.

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Ngaios HTTP WARNING: HTTP/1.1 403 Forbidden

To solve this..

simply create index.html file under http root directory.

#cd /var/www/html
#touch index.html

Restart web services.

#service httpd restart

Now restart you nagios services.

#/etc/init.d/nagios restart

After this you will see this meaasge on you nagios. (status information)

HTTP OK HTTP/1.1 200 OK - 265 bytes in 0.004 seconds.


Enjoy it.....

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Fedora LVM partitions,mount through ubuntu Live CD.

Use the following steps.

login as root like this--
$sudo su -

#apt-get install lvm2

#modprobe dm-mod

#vgchange -a y

#lvdisplay ( it will show you the lvm partition)

Now mount the LVM ...

#mkdir /tmp

#mount /dev/VolGroup00/Logvol00 /tmp

Now check /tmp dir for access data.

Enjoy......:)

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Wireless Issue -Dell Vostro 1520 - Fedora 11 (Intel WiFi Link 5100)

Since I have had large amount of hassles getting the wireless working with Intel WiFi Link 5100 wifi card on the Dell Vostro 1520 (wouldn't be the only affected model).

Problem:

Problem is that NetworkManager cannot find out if the killswitch is turned on or off so it assumes its off y default and disables the wireless.

Some other methods that half worked (could scan for available networks but could not join them) are:
wlassistant
wpa_supplicant (directly with config files)
traditional networking for wireless

To get working via all programs (NetworkManager included):

Step 1: Install the firmware of the wireless (iwl5000-firmware):
yum install iwl5000-firmware -y

Step 2: Disable dell_laptop kernel module:
modprobe -rv dell_laptop

Step 3: Stop dell_laptop kernel module from being automatically loaded on boot:
echo "blacklist dell_laptop" >> /etc/modprobe.d/blacklist.conf

Step 4: Start/Restart NetworkManager
/etc/init.d/NetworkManager restart
or
service NetworkManager restart

Step 5: Connect to a wireless network to verify all is working.

Hope this helps if you hit the same problem.

Special thanks to Kelly Reed.

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Wireless Issue -Dell Vostro 1510 - Fedora 11

Face wifi issue with dell vostro 1510 + fc11

#lspci (command output)

Network controller : Broadcom corporation BCM 4312 802.11b/g (rev 01)

This solution work for me:--

#rpm -Uvh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm

#yum update

#yum install kmod-wl ( around 22MB )


Reboot the machine & Wireless connection work me.

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upgrade centOS 5.3 to 5.4

use the following steps for upgrade,

yum clean all
yum update glibc\*
yum update yum\* rpm\* python\*
yum clean all
yum update
shutdown -r now

After reboot check

#cat /etc/redhat-release
CentOS release 5.4 (Final)


Done!!!!

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Can't locate Net/SNMP.pm in @INC (@INC contains + Nagios

If you get above error, and in your script syntax like this,

use strict;
use Net::SNMP;
use Getopt::Long;

Then use the following step to install Net SNMP

Solution :-- Login as a root user on machine.

#perl -MCPAN -e shell

cpan> install Bundle::CPAN

cpan[1]> reload cpan

cpan[1]> reload index

cpan[1]> install Net::SNMP

cpan[1]> install Getopt::Long


After all this try to execute your script ..hope your problem resolved.

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VNC client on a linux machine

#yum install tigervnc

then type
#vncviewer hit enter

a box open for you ... enter the hostname & hit enter.

then dialog prompting you for a password. enter the passwd and enter

Now RDP connection open for you.

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Linux Remote desktop for manage window machine

Manage window xp/vista/server2003

Make sure rdesktop package installed on your linux machine.

to insatll rdesktop use following command

# yum install rdesktop

Now use following command to connect window machine

#rdesktop ipaddress of window machine

#rdesktop 10.11.131.11

But make sure Remote desktop enable on window machine. to enable RDP use following steps.

# Right Click on My Computer
# Select properties
# Select Remote tab
# Enable Remote desktop.
# Save the changes.


Cheers...... :)

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Reflash the firmware using the tftp method for Linksys wet54gl

*
Configure your PC with a static IP address between 192.168.1.2 and 192.168.1.254. E. g. 192.168.1.2 (gateway and DNS is not required).
*
Download the openwrt-wrt54g-squashfs.bin firmware image to your PC
*
Execute the TFTP commands (the commands are for Linux) below:

tftp 192.168.1.1
tftp> binary
tftp> trace
tftp> put openwrt-wrt54g-squashfs.bin

*
Plug the power on and the TFTP transfer should start immediately
*
Wait 2 minutes. The router will reboot itself automatically after the upgrade is complete.
*
You are done! You should be able to telnet to your router (IP address: 192.168.1.1) and start configuring.

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Fatal error, run database recovery

If you get this error while installing new packages or through yum install pkg*

[root@inf1sysadm1 Download]# rpm -ivh thunderbird-2.0.0.18-2.fc11.i386.rpm
rpmdb: Thread/process 3301/3085969184 failed: Thread died in Berkeley DB library
error: db4 error(-30974) from dbenv->failchk: DB_RUNRECOVERY: Fatal error, run database recovery
error: cannot open Packages index using db3 - (-30974)
error: cannot open Packages database in /var/lib/rpm
rpmdb: Thread/process 3301/3085969184 failed: Thread died in Berkeley DB library
error: db4 error(-30974) from dbenv->failchk: DB_RUNRECOVERY: Fatal error, run database recovery
error: cannot open Packages database in /var/lib/rpm

Try this solution :---

# rm /var/lib/rpm/__db*

# rpmdb --rebuilddb (wait for complete)

Now your problem solved... :)

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/var/cache/yum/updates/metalinks.xml does not exist

After FC11 upgrade, software update is failing

Run Following command

#yum clean all

After that

#yum update

Hope your problem resolved.

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Samba session setup failed: NT_STATUS_LOGON_FAILURE

If you face problem while access samba in window machine follow the following steps.

Login in your linux box.

run this command.

[root@rk ~]# smbclient -L localhost or machine ip 10.1.7.105
Enter root's password:
session setup failed: NT_STATUS_LOGON_FAILURE (if u get this msg)

Make sure your firwall stop..
#iptables -L ( to see current rules)
#iptables -F ( to delete are rules)

now restart samba services.
#service smb restart

now check ...it working for you.

To customize your smb.conf you can use following:-

[global]
workgroup = raman
server string = Samba Server Version %v
log file = /var/log/samba/log.%m
max log size = 50
security = user
passdb backend = tdbsam
cups options = raw
username map = /etc/samba/smbusers

[homes]
comment = Home Directories
browseable = no
writable = yes

[printers]
comment = All Printers
path = /var/spool/samba
browseable = no
printable = yes

[media]
path = /media
writeable = yes
valid users = test



Cheers..... enjoy..........

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mod_rewrite Not Working in .htaccess

I faced a hair-tearing problem. mod_rewrite was loaded and yet it was not working in .htaccess files (and httpd.conf initially). Here is the solution along with how you can debug mod_rewrite problems.

Debugging procedure:
Add these two line to your httpd.conf immediately after RewriteEngine On.
RewriteLog "/var/log/httpd/rewrite_log"
RewriteLogLevel 9
After that I added the required RewriteRule etc.

The reason for testing directly in httpd.conf is to ensure that mod_rewrite is working in the first place. After some debugging I realized my expression was wrong. So now I found mod_rewrite was working in httpd.conf. However it still wasn't working in .htaccess files.

Solution:
I found AllowOverride was set to None in httpd.conf. I changed it to All (after all I am the only user of the machine). And it finally started working everywhere (after a restart).

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Logical volume Manager (LVM)

Logical volume Manager

1st we will create create partition called PV (Physical Volume)

IMP:-- Patition type of this PV should be 8e (u can chage through fdisk than press t)


Now prepare new partition for LVM

#pvcreate /dev/hda10 /dev/hda11 /dev/hda12

revert this last action for training purposes

#pvremove /dev/hda10 /dev/hda11 /dev/hda12


To see current state of PV

#pvdisplay



Now create Volume group (vg)

#vgcreate raman /dev/hda10 /dev/hda11 /dev/hda12


Behind the scenes, the LVM system allocates storage in equal-sized "chunks", called extents. We can specify the particular extent size to use at volume group creation time. The size of an extent defaults to 4Mb, which is perfect for most uses.You can use the -s flag to change the size of the extent. The extent affects the minimum size of changes which can be made to a logical volume in the volume group, and the maximum size of logical and physical volumes in the volume group. A logical volume can contain at most 65534 extents, so the default extent size (4 MB) limits the volume to about 256 GB; a size of 1 TB would require extents of atleast 16 MB. So to accomodate a 1 TB size, the above command can be rewriten as :

# vgcreate -s 16M my_vol_grp /dev/hda1 /dev/hda2



To see current state of VG

#vgdisplay


Now create LV (logical volume)

#lvcreate -L 500M -n raman1 raman

(-L logical size, -n Logical vol name)


To see current state of VG

#lvdisplay


Format

#mkfs.ext3 /dev/raman/raman1

#mount /dev/raman/raman1 /data

do not forget to append the corresponding line in the /etc/fstab

/dev/raman/raman1 /data ext3 defaults 0 0



For Extend LV

#lvextend -L 275M /dev/raman/raman1


#ext2online /dev/raman/raman1


#df -h (for check)

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config.inc.php in Phpmyadmin configuration

/*
* This is needed for cookie based authentication to encrypt password in
* cookie
*/
$cfg['blowfish_secret'] = 'LAMP'; /* YOU SHOULD CHANGE THIS FOR A MORE SECURE COOKIE AUTH! */

/*
* Servers configuration
*/
$i = 0;

/*
* First server
*/
$i++;

/* Authentication type and info */
# commented out by lampp security
#$cfg['Servers'][$i]['auth_type'] = 'config';
$cfg['Servers'][$i]['auth_type'] = 'cookie';
$cfg['Servers'][$i]['user'] = 'root';
$cfg['Servers'][$i]['password'] = '';

/* User for advanced features */
$cfg['Servers'][$i]['controluser'] = 'pma';
$cfg['Servers'][$i]['controlpass'] = '';

/* Advanced phpMyAdmin features */
$cfg['Servers'][$i]['pmadb'] = 'phpmyadmin';
$cfg['Servers'][$i]['bookmarktable'] = 'pma_bookmark';
$cfg['Servers'][$i]['relation'] = 'pma_relation';
$cfg['Servers'][$i]['table_info'] = 'pma_table_info';
$cfg['Servers'][$i]['table_coords'] = 'pma_table_coords';
$cfg['Servers'][$i]['pdf_pages'] = 'pma_pdf_pages';
$cfg['Servers'][$i]['column_info'] = 'pma_column_info';
$cfg['Servers'][$i]['history'] = 'pma_history';
$cfg['Servers'][$i]['designer_coords'] = 'pma_designer_coords';

/*
* End of servers configuration
*/

?>

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How can we enable fsockopen function in PHP

To check fsock function,Open your php.ini

;;;;;;;;;;;;;;;;;;
; Fopen wrappers ;
;;;;;;;;;;;;;;;;;;

; Whether to allow the treatment of URLs (like http:// or ftp://) as files.
allow_url_fopen = On (Make sure this is ON)

; Define the anonymous ftp password (your email address)
;from="abc@com"

; Default timeout for socket based streams (seconds)
default_socket_timeout = 60


With following script you can check your fsock functionalty.

vi test.php (under web server dir) Run this script...


$fp = fsockopen ("localhost", 80, $errno, $errstr, 30);
if (!$fp) {
echo "$errstr ($errno)
\n";
}else
{
echo "connected";
}

fclose ($fp);
?>


If you get connected message ..that mean you fsock function enable.

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Linux syslog server & window agent

To configure a syslog log server... follow thses steps.

Edit syslog.conf

#vi /etc/syslog.conf

#for window use this setting
local7.* /var/log/win2k/win.log

save the file.

(manullay create dir & file... win2k/win.log)

After that Edit /etc/sysconfig/syslog

#vi /etc/sysconfig/syslog

Find term SYSLOGD_OPTIONS... use following term to allow remote host connect to server.

SYSLOGD_OPTIONS="-m 0 -r -x"

Save the file & restart the services.

#service syslog restart

or

#/etc/init.d/syslog restart


After that download Syslog agent for window.
use following link for download.

http://www.syslogserver.com/download.html (download Datagram SyslogAgent )

or

http://www.intersectalliance.com/projects/SnareWindows/index.html#Download

I tried both and both are working for me.

I guide you few steps for Snare, follow these.

After installation.

– Click start, programs, Intersect Alliance, Snare for Windows
– Network Configuration
– Destination Snare Server address (set this to the linux server ip address).
– Destination Port: 514
– SYSLOG Facility: Local7
– SYSLOG Priority: Information

Click Change Configuration.

Click Apply the Latest Audit Configuration (on the left hand side).
Ok, the Windows part is done.




Now do some changes in your window box....all log are captured in syslog server.
You can check the file through

#less /var/log/win2k/win.log


Hope this work for you. Enjoy...

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