Note: Port, Service Name and . . . → Read More: [Urdu CBT] Embracing Linux: Fedora: Part 12: System Administration – VSFTPD Server (CLI)]]> This part covers the VSFTPD server. The commands / method is applicable on RHEL, Fedora and CENTOS.

• RPM, Port, Service Name and Process Name
• Configuration Files location, Log file locations
• Anonymous FTP
• chroot_local_user
• Using ftp and sftp to connect and manage websites hosted as Apache vhosts on the same server.

Note: Port, Service Name and Process Name used by VSFTP are covered in a short video in Part 2. You may want to see it first.

The second video has one error in it. Port 21 TCP is actually FTP control port, not data port. Port 20 is the legacy FTP data port, as it used to be in FTP “active mode”. (More detail in a separate upcoming video).

Device Mapper Multipath (DM-MP) allows nodes to route I/O over multiple paths to a storage controller. A path refers to the  connection from an HBA port to a storage controller port. As paths  fail and new paths come up, DM-MP . . . → Read More: Linux MultiPathing HowTo by Asim Abbas]]> Linux MultiPathing Howto. By Syed Asim Abbas
Date: 24-10-2009 ( asimabbas31 _at_ gmail _dot_ com)

Device Mapper Multipath (DM-MP) allows nodes to route I/O over multiple paths to a storage controller. A path refers to the  connection from an HBA port to a storage controller port. As paths  fail and new paths come up, DM-MP reroutes the I/O over the available paths.

Easy way to configure Multipathing
————————————

[root@power root]# rpm -qa |grep multipath
device-mapper-multipath-0.4.8-7.fc10.i386

[root@power root]# fdisk -l

Disk /dev/sda: 60.0 GB, 60011642880 bytes
255 heads, 63 sectors/track, 7296 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x3f443f43

Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdg: 107.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdn: 107.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdh: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdo: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

MultiPathing packaged avilable on Distribution

###Check the SCSI IDs to see the disk are pairs. /dev/sda is my system disk so no need to configure it for multipathing. Sdg , sdn, sdh and sdo are SAN connected disks.

[root@power root]# scsi_id -g -u -s /block/sdg
360060e8005bcaf000000bcaf00006024
[root@power root]# scsi_id -g -u -s /block/sdn
360060e8005bcaf000000bcaf00006024

[root@power root]# scsi_id -g -u -s /block/sdh
360060e8005bcaf000000bcaf00005033
[root@power root]# scsi_id -g -u -s /block/sdo
360060e8005bcaf000000bcaf00005033

##Ok sdg,sdn Pair and sdh,sdo Pair .

###To implement multipath environment, you must define the alias names for the multipath devices by editing the multipath.conf file that resides in the /etc/ directory:

[root@power root]# vi /etc/multipath.conf

# Blacklist all devices by default. Remove this to enable multipathing
# on the default devices.
blacklist {
devnode “*”
}

##############Comment The above lines

# Blacklist all devices by default. Remove this to enable multipathing
# on the default devices.
#blacklist {
#        devnode “*”
#}

#########Define the Disks Aliases ##########

multipaths {

multipath {
wwid                    360060e8005bcaf000000bcaf00006024
alias                   ora1
}

multipath {
wwid                    360060e8005bcaf000000bcaf00005033
alias                   ora2
}

}

####### Save the configuration

[root@power root]# chkconfig multipathd on

[root@power root]# service multipathd restart
Stopping multipathd daemon:                                [FAILED]
Starting multipathd daemon:                                [  OK  ]
[root@power root]#

[root@power root]# fdisk -l

Disk /dev/sda: 60.0 GB, 60011642880 bytes
255 heads, 63 sectors/track, 7296 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x3f443f43

Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdg: 107.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdn: 107.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdh: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdo: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

##########No update same result. Restart the system and run fdisk -l

[root@power root]# fdisk -l

Disk /dev/sda: 60.0 GB, 60011642880 bytes
255 heads, 63 sectors/track, 7296 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x3f443f43

Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdg: 107.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdn: 107.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdh: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/sdo: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/dm-0: 70.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/dm-1: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/mpath/ora1: 70.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

Disk /dev/mpath/ora2: 153.0 GB, 60011642880 bytes
Device Boot      Start         End      Blocks   Id  System

#########Ok four more disks are aviavlable. Don’t confude just used your paths  /dev/mpath/ora1  /dev/mpath/ora2

[root@power root]# ls /dev/mpath*

ora1    ora2

####Disks multipath names are available now. Mount the devices using new name.

[root@power root]# mount /dev/mpath/ora1 /ora1

[root@power root]# mount /dev/mpath/ora2 /ora2

For testing unplugged one fiber link and see the results.