tutor:Cluster

Hard drive layout

Logical Volumes

http://ds9a.nl/lvm-howto/HOWTO//cvs/lvm-howto/lvm-howto.html

For mkfs -t xfs /dev/VolGroup00/local command check: rpm -qa |grep xfsprogs # install it: # for xen.x86_64 (for others check: <code>uname -a</code>) yum install kmod-xfs-xen.x86_64 xfsdump xfsprogs

To create the VG:

vgdisplay -v
 
pvcreate /dev/sda3
pvcreate /dev/sdb1
vgcreate sn /dev/sda3 /dev/sdb1
vgdisplay -v sn
lvcreate -l 100%VG -n local sn
vgdisplay -v sn
 
mke2fs /dev/sn/local
 
echo "/dev/sn/local /local ext3    defaults        1 1" >> /etc/fstab
mount /dev/sn/local /local

Backup

Backup refers to making copies of data so that these additional copies may be used to restore the original after a data loss event. These additional copies are typically called "backups." Backups are useful primarily for two purposes. The first is to restore a state following a disaster (called disaster recovery). The second is to restore small numbers of files after they have been accidentally deleted or corrupted.

There is different configuration for backup procedure organization. It can be the following:

1. merge logs in the one server (e.g. file server)
2. backup this server
3. if necessary - backup all others servers in the rack.

Logging

Merge logs in one place

Configure the server <syslog server>

1. Log on to the server as a super user.
2. Change the option in vi /etc/sysconfig/syslog as: SYSLOGD_OPTIONS="-m 0 -r"
3. Restart the syslog service using the command /etc/rc.d/init.d/syslog restart.

Forwarding syslog Messages from Linux device

1. Log on to the Linux device (whose messages you want to forward to the <syslog server>) as a super user.
2. Enter the command - vi /etc/syslog.conf to open the configuration file called syslog.conf.
3. Enter *.* and press the Tab key and enter the name of the host machine where the server is running. For example: *.* @<syslog server>
4. Restart the syslog service using the command /etc/rc.d/init.d/syslog restart.

Forwarding syslog messages from routers

To enable syslog monitoring in router and redirect the log message to the syslog server:

1. Telnet to the router machine as telnet <router>.
2. Type the command enable at the prompt to set to 'enable' mode.
3. You will be prompted to enter the password. Enter the correct password.
4. Now, type the command config at the prompt.
5. Choose terminal configuration.
6. After this, type logging <IP address of the host device where <syslog server> server is running> at the command prompt. For example, logging <192.168.5.120>. This is done to enable forwarding of messages to the <syslog server> server.