Xen workshop - Revision history

Guillaume at 21:09, 3 February 2009

2009-02-03T21:09:25Z

Guillaume at 15:15, 3 February 2009

2009-02-03T15:15:12Z

Guillaume: /* Day 2 */

2009-02-03T14:59:05Z

‎Day 2

Guillaume: /* Day 2 */

2009-02-03T14:58:30Z

‎Day 2

Guillaume at 14:57, 2 February 2009

2009-02-02T14:57:51Z

Guillaume: /* Shell commands syntax */

2009-01-27T18:19:52Z

‎Shell commands syntax

Guillaume at 18:06, 27 January 2009

2009-01-27T18:06:35Z

Guillaume at 16:05, 27 January 2009

2009-01-27T16:05:55Z

Guillaume: Documenting notes on the Xen workshop

2009-01-27T15:49:39Z

Documenting notes on the Xen workshop

New page

On January 2009, we held a workshop lectured by [http://conexa.pt Conexa] on [[Xen]] servers. During the course of the workshop we learned about the specifications and the architecture of our virtual machines server but also about logical volumes management and creating and managing [[xen]] virtual machines.

==Day 1==

===Architecture and hardware specifications===

*Quad-core Opteron AMD with 20GB ram and 2 TB RAID5 [[#Logical volumes management|Physical Volume]] composed by 4x750GB enterprise-graded hard-drives,
* Suse Enterprise Server v10.2 with Xen Hypervisor installed,
* Network address at '''192.168.20.125'''.

===Logical volumes management===

====LVM architecture====
; Physical Volume (PV): '''/dev/sda''' or '''/dev/sdb'''
; Volume Group (VG): '''/dev/sda/dados01'''
; Logical Volume (LV): '''/dev/sda/dados01/vmmrtsrv01'''

====RAID types====
There hardware RAID controllers and software RAID controllers. The latter aren't that worthy since all is lost when the mainboard fails. Hardware RAIDS are great, as long as the controller is a separate board from the mainboard. If not, if the mainboard fails and if you can't find exactly the same mainboard, byebye data. [http://conexa.pt Conexa] recommends <goto>3Ware RAID controller boards</goto>.

; RAID 0: Striping. Good for performance. Terrible for data security. It writes data split accross an array of hard-drives. If one hard-drive fails all the data is lost. However writing speed and performance are excellent.

; RAID 1: Duplicate. Good for security. Everything is mirrored as is in a second hard-disk. If one disk fails, then the data exists in the other hard-disk. Not storage capacity efficient: '''2GB of raw capacity for 1 GB of data storage'''.

; RAID 10: Striping + Duplicate. Good for security and for performance. Basically its a RAID 0 [[#LVM architecture|PV]] that is replicated. Thus, it requires two identical arrays of hard-drives. '''2GB raw for 1GB data'''.

; RAID 5: Redundant striping. Good for performance AND security. It's basically a RAID 0 BUT redundant information is stored along each file, so that if one hard-disk fails the system can still recover all the information. However, as the system grows in hard-drives, the probability that 2 hard-drives fail gets bigger. Best compromise for performance, security AND storage capacity. Ratios vary but we have a '''4GB raw : 3GB data''' ratio.

; RAID 50: Striping the redundant striping. Its basically a composition of a RAID 0 applied on top of RAID 5 PVs.

; Hot swap: A hot swap hard-disk is a hard-disk left alone that you can readily change whenever one of the hard-disks fails. It's very convenient. Works best with RAID 1, 10, 5 or 50. ''Currently the Maretec xen server doesn't has any''.

===Creating and configuring new xen virtual machines===
* Console access through a VNC client via '''192.168.20.125:590?'''

@@ Line 154: / Line 154: @@
 ==External references==
 *[http://www.xen.org/ Xen project]
 *[http://conexa.pt Conexa]

@@ Line 114: / Line 114: @@
   > losetup -a
-How to detach a device?
+===How to detach a device?===
   > xm block-list VMMRTSRV06
   > xm block-detach VMMRTSRV06 5632 -f
   > xm block-list VMMRTSRV06
-How to attach a device?
+===How to attach a device?===
   > xm block-list VMMRTSRV05
   > xm block-attach VMMRTSRV05 phy:/dev/mapper/dados01-vmmrtsrv03 hdd:disk mode r
@@ Line 125: / Line 125: @@
   > xm block-list VMMRTSRV05
-text-mode console access (como configurar?)
+===text-mode console access (como configurar?)===
 Fiddle with the grub.conf file...
   > sudo /usr/sbin/xm console VMMRTSRV06
@@ Line 132: / Line 132: @@
   > cd /opt/novell/vm-driver-pack/xen
-How to change a domain between the DMZ/LAN?
+===How to change a domain between the DMZ/LAN?===
   > xm list > config_save.cfg
   > xm delete
   > xm new -f
-How to extend the storage size of a xen domain?
+===How to extend the storage size of a xen domain?===
   > pvextend
-How to export a xen domain?
+===How to export a xen domain?===
   > dd if=/dev/mapper/dados01-lv01 of=/mnt/usb/export.iso
-How create and use vm snapshots
+===How create and use vm snapshots===
   > lvcreate -n lv01-snapshot -s lv01 -L 10G dados01
   > lvcreate igual ao lv01 (lv01_01)

@@ Line 108: / Line 108: @@
 ==Day 2==
-> visudo --> configures sudoers
+ > visudo --> configures sudoers
-> sudo /usr/sbin/xm list -l VMMRTSRV02
+ > sudo /usr/sbin/xm list -l VMMRTSRV02
 Note: paper-print basic information (when everything fails...)
-> losetup -a
+ > losetup -a
 How to detach a device?
-> xm block-list VMMRTSRV06
+ > xm block-list VMMRTSRV06
-> xm block-detach VMMRTSRV06 5632 -f
+ > xm block-detach VMMRTSRV06 5632 -f
-> xm block-list VMMRTSRV06
+ > xm block-list VMMRTSRV06
 How to attach a device?
-> xm block-list VMMRTSRV05
+ > xm block-list VMMRTSRV05
-> xm block-attach VMMRTSRV05 phy:/dev/mapper/dados01-vmmrtsrv03 hdd:disk mode r
+ > xm block-attach VMMRTSRV05 phy:/dev/mapper/dados01-vmmrtsrv03 hdd:disk mode r
-> xm block-attach VMMRTSRV05 file:/mnt/somefile.iso hdc:cdrom mode r
+ > xm block-attach VMMRTSRV05 file:/mnt/somefile.iso hdc:cdrom mode r
-> xm block-list VMMRTSRV05
+ > xm block-list VMMRTSRV05
 text-mode console access (como configurar?)
 Fiddle with the grub.conf file...
-> sudo /usr/sbin/xm console VMMRTSRV06
+ > sudo /usr/sbin/xm console VMMRTSRV06
 Drivers: network interface, hard-disk. Critical for performance in windows environment.
-> cd /opt/novell/vm-driver-pack/xen
+ > cd /opt/novell/vm-driver-pack/xen
 How to change a domain between the DMZ/LAN?
-> xm list > config_save.cfg
+ > xm list > config_save.cfg
-> xm delete
+ > xm delete
-> xm new -f
+ > xm new -f
 How to extend the storage size of a xen domain?
-> pvextend
+ > pvextend
 How to export a xen domain?
-> dd if=/dev/mapper/dados01-lv01 of=/mnt/usb/export.iso
+ > dd if=/dev/mapper/dados01-lv01 of=/mnt/usb/export.iso
 How create and use vm snapshots
-> lvcreate -n lv01-snapshot -s lv01 -L 10G dados01
+ > lvcreate -n lv01-snapshot -s lv01 -L 10G dados01
-> lvcreate igual ao lv01 (lv01_01)
+ > lvcreate igual ao lv01 (lv01_01)
-> dd if=lv01_01
+ > dd if=lv01_01
 ==Miscelaneous notes==

@@ Line 108: / Line 108: @@
 ==Day 2==
-===Changing size of LV and size of linux VM===
+> visudo --> configures sudoers
-*To-be-done
+> sudo /usr/sbin/xm list -l VMMRTSRV02
 ==Miscelaneous notes==

← Older revision		Revision as of 14:57, 2 February 2009
Line 121:		Line 121:

	[[Category:Linux]]		[[Category:Linux]]
		+	[[Category:Xen]]
		+	[[Category:VM]]

@@ Line 35: / Line 35: @@
 ====Shell commands syntax====
   > uname -ar
-  uname> Linux dual_64 2.6.20.7 #12 SMP Tue Apr 24 18:25:55 WEST 2007 x86_64 x86_64 x86_64 GNU/Linux You have new mail in /var/spool/mail/guillaume
+  uname> Linux dual_64 2.6.20.7 #12 SMP Tue Apr 24 18:25:55 WEST 2007 x86_64 x86_64 x86_64 GNU/Linux
   > free

@@ Line 9: / Line 9: @@
 * Network address at '''192.168.20.125'''.
 * [[#RAID types|RAID 5]] of 1.97TB with no hot-swap disk available.
 ====RAID types====
@@ Line 77: / Line 78: @@
   > dd
 ===Creating and configuring new xen virtual machines===
 * Console access through a VNC client via '''192.168.20.125:590?'''
 * Available devices can be set from '''.iso''' files, or from [[#LVM architecture|LVs]]
 ===Scheduling and managing the cpu resources to VMs===
 ==Day 2==
-===Changing size of LV and size of linux VM==
+===Changing size of LV and size of linux VM===
 *To-be-done

@@ Line 1: / Line 1: @@
-On January 2009, we held a workshop lectured by [http://conexa.pt Conexa] on [[Xen]] servers. During the course of the workshop we learned about the specifications and the architecture of our virtual machines server but also about logical volumes management and creating and managing [[xen]] virtual machines.
+On January 2009, we held a workshop lectured by [http://conexa.pt Conexa] on [[Xen]] servers. During the course of the workshop we learned about the specifications and the architecture of our virtual machines server but also about logical volumes management and creating and managing [[xen]] virtual machines (VM).
 ==Day 1==
@@ Line 8: / Line 8: @@
 * Suse Enterprise Server v10.2 with Xen Hypervisor installed,
 * Network address at '''192.168.20.125'''.
+* [[#RAID types|RAID 5]] of 1.97TB with no hot-swap disk available.
 ====RAID types====
@@ Line 30: / Line 24: @@
 ; Hot swap: A hot swap hard-disk is a hard-disk left alone that you can readily change whenever one of the hard-disks fails. It's very convenient. Works best with RAID 1, 10, 5 or 50. ''Currently the Maretec xen server doesn't has any''.
 ===Creating and configuring new xen virtual machines===
 * Console access through a VNC client via '''192.168.20.125:590?'''