virtio-scsi going to be really a cool implementation on virtio stream. Indeed virtio-blk was arranging that position. How-ever virtio-blk lagged/skipped lots of scsi command ioctls which paved the way to virtio-scsi. Along with virtio-scsi implementation, other downsides of virtio-blk have been lifted, for ex: the number of disk limitation..etc.. To know more about virtio-scsi, I …
Today one of my friend came into this error and I was called up to find a solution.. [root@host]# virsh create /etc/libvirt/qemu/rhel5.4-x86_64-kvm.xml error: Failed to create domain from /etc/libvirt/qemu/rhel5.4-x86_64-kvm.xml error: internal error Process exited while reading console log output: Supported machines are: pc Standard PC (alias of pc-0.14) pc-0.14 Standard PC (default) fedora-13 Standard PC …
Today one of my friend asked me to interpret below assembly instruction for him, so this post 🙂 The instruction have below format, It is one of indirect addressing modes, so this should be read in such a way that, What that basically means is that IR * Width + offset
RHEL 6.3 KVM is out with lots of new/coool features ( virtio-scsi, s3/s4 support, PMU , guest agent, vcpu hot plug, per-kvm..etc 🙂 .. Brief idea on each is listed here .. KVM scalability enhancements KVM scalability enhancements in Red Hat Enterprise Linux 6.3 include: The maximum supported virtual guest size increased from 64 to …
Hey my friends, Videos are always better place to learn about a technology 🙂 .. You can watch “ovirt” videos from below urls.. I am sure it will help you to achieve good understanding on ovirt-{engine, node, architecture..etc} 1) OVIRT ARCHITECTURE ( Overview ) ovirt introduction virtualization in an ovirt way 2) OVIRT …
Open vSwitch (OVS) is a software switch. It consist of user space tools provided by openvswitch rpm and kernel modules provided by kmod-openvswitch rpm. Unlike the bridge available in old versions of distros ( fedora, rhel..etc ) it provides many advanced configuration options like tagged vlan. Full details available at http://www.openvswitch.org/
Open vSwitch is a network switch; at its lowest level, it is concerned with routing packets between interfaces. It is aimed at virtualization users, so, naturally, it is used in the creation of virtual networks. A switch can be set up with a number of virtual network interfaces, most of which are used by virtual machines to communicate with each other and the wider world. These virtual networks can be connected across hosts and across physical networks. One of the key features of Open vSwitch appears to be the ability to easily migrate virtual machines between physical hosts and have their network configuration (addresses, firewall rules, open connections, etc.) seamlessly follow.
Below Process will outline the steps required in CentOS/RHEL..etc
STARTING THE SERVICE
modprobe -r bridge (OVS kernel modules conflict with the “bridge” module)
modprobe openvswitch_mod
modprobe brcompat_mod (OVS bridge compatibility support module. Without this lbvirt cannot use OVS)
Once kernel module part is loaded, lets try to start the subjected service as shown below:
/etc/init.d/openvswitch start
/etc/openvswitch/conf.db does not exist … (warning).
Creating empty database /etc/openvswitch/conf.db [ OK ]
Starting ovsdb-server [ OK ]
Configuring Open vSwitch system IDs [ OK ]
Starting ovs-vswitchd [ OK ]
So, ovs-vswitchd service is started successfully..
Below command needs ‘brcompat_mod’ and will enable libvirt to use brctl to manage OVS.
ovs-brcompatd –pidfile –detach
Below are the steps which I followed to configure vlan ..
HOW TO CREATE TAGGED VLANS
On the HOST
ovs-vsctl add-br br0
ovs-vsctl add-port br0 vlan10 tag=10 — set interface vlan10 type=internal [creating a taged vlan 10]
Now, lets list the bridge configuration in the system via ‘brctl’ command..
brctl show
If something goes wrong (easiest way ) stop openvswitch service, delete /etc/openvswitch/conf.db and start the service again. Do the configuration again.
To test: Execute below steps in VM1
vconfig add eth0 10 [add vlan interface]
ifconfig eth0.10 192.168.10.100 netmask 255.255.255.0 broadcast 192.168.10.255 up [assign IP]
vconfig add eth0 20
ifconfig eth0.20 192.168.20.100 netmask 255.255.255.0 broadcast 192.168.20.255 up
VM2
vconfig add eth0 10 [add vlan interface]
ifconfig eth0.10 192.168.10.101 netmask 255.255.255.0 broadcast 192.168.10.255 up [assign IP]
vconfig add eth0 20
ifconfig eth0.20 192.168.20.101 netmask 255.255.255.0 broadcast 192.168.20.255 up
Now try pinging VM1 to VM2
*************************************************************************************************************** Below Process will outline Fedora 17, 18, 19 Versions:
Unlike centos/rhel , the openvswitch support is added in libvirt. So, you dont need ‘brcompat_mod’ mentioned in first/above section to use it with libvirt.
Aug 02 08:26:25 Xman openvswitch.init[31565]: /etc/openvswitch/conf.db does not exist … (warning).
Aug 02 08:26:25 Xman openvswitch.init[31565]: Creating empty database /etc/openvswitch/conf.db [ OK ]
Aug 02 08:26:25 Xman openvswitch.init[31565]: Starting ovsdb-server [ OK ]
Aug 02 08:26:25 Xman ovs-vsctl[31592]: 00001|vsctl|INFO|Called as ovs-vsctl –no-wait — init — set Open_vSwitch . db-version=6.12.0
Aug 02 08:26:25 Xman ovs-vsctl[31597]: 00001|vsctl|INFO|Called as ovs-vsctl –no-wait set Open_vSwitch . ovs-version=1.10.0 “external-ids:system-id…unknown\””
Aug 02 08:26:25 Xman openvswitch.init[31565]: Configuring Open vSwitch system IDs [ OK ]
Aug 02 08:26:25 Xman openvswitch.init[31565]: Starting ovs-vswitchd [ OK ]
Aug 02 08:26:25 Xman openvswitch.init[31565]: Enabling remote OVSDB managers [ OK ]
Aug 02 08:26:25 Xman openvswitch.init[31565]: Enabling gre with iptables [ OK ]
Aug 02 08:26:25 Xman systemd[1]: Started Open vSwitch.
[root@Xman 3.9.9-301.fc19.x86_64]#
Specifically for BIOS information below commands can be used
#biosdecode
[root@humbles-lap Desktop]# biosdecode
# biosdecode 2.11
ACPI 2.0 present.
OEM Identifier: Sony
RSD Table 32-bit Address: 0xDEF1CF18
XSD Table 64-bit Address: 0x00000000DEF1CE18
SMBIOS 2.6 present.
Structure Table Length: 731 bytes
Structure Table Address: 0x000EBCA0
Number Of Structures: 17
Maximum Structure Size: 113 bytes
PNP BIOS 1.0 present.
Event Notification: Not Supported
Real Mode 16-bit Code Address: F000:BA66
Real Mode 16-bit Data Address: F000:0000
16-bit Protected Mode Code Address: 0x000FBA8E
16-bit Protected Mode Data Address: 0x000F0000
PCI Interrupt Routing 1.0 present.
Router ID: 00:1f.0
Exclusive IRQs: None
Compatible Router: 8086:2912
Slot Entry 1: ID 00:1f, on-board
Slot Entry 2: ID 00:1d, on-board
Slot Entry 3: ID 00:1a, on-board
Slot Entry 4: ID 00:1b, on-board
Slot Entry 5: ID 00:1c, on-board
Slot Entry 6: ID 02:00, slot number 33
Slot Entry 7: ID 00:16, on-board
Slot Entry 8: ID 03:00, slot number 255
Slot Entry 9: ID 00:02, on-board
Slot Entry 10: ID 04:00, slot number 8
Slot Entry 11: ID 05:00, slot number 16
Slot Entry 12: ID 00:01, on-board
Slot Entry 13: ID 01:00, slot number 16
Slot Entry 14: ID 00:03, on-board
[root@humbles-lap Desktop]#
Then comes “dmidecode” with specific options.. The interesting switch of “dmidecode” is “-t” here.. You can use the same option with specifying a “TYPE” value with it..
Below are the different “TYPES” which can be used with “-t” option..
Type Information
────────────────────────────────────────
0 BIOS
1 System
2 Base Board
3 Chassis 4 Processor
5 Memory Controller
6 Memory Module
7 Cache
8 Port Connector
9 System Slots
10 On Board Devices
11 OEM Strings
12 System Configuration Options
13 BIOS Language
14 Group Associations
15 System Event Log
********** Truncated.. Refer #man dmidecode for more information..
There are couple of ‘virsh’ commands which can be used to get some basic information about the hypervisor which are in use/connected..
I will directly show the command output to get that information..
[root@humbles-lap ~]#virsh nodeinfo
CPU model: x86_64
CPU(s): 4
CPU frequency: 1599 MHz
CPU socket(s): 1
Core(s) per socket: 2
Thread(s) per core: 2
NUMA cell(s): 1
Memory size: 3909832 kB
