Installing and Configuring LDOMs (Oracle VM for SPARC)
Logical Domains (LDoms or LDOM) is the server virtualization and partitioning technology for SPARC V9 processors. It was first released by Sun Microsystems in April 2007. After the Oracle acquisition of Sun in January 2010, the product has been re-branded as Oracle VM Server for SPARC from version 2.0 onwards.
Each domain is a full virtual machine with a reconfigurable subset of hardware resources. Domains can be securely live migrated between servers while running. Operating systems running inside Logical Domains can be started, stopped, and rebooted independently. A running domain can be dynamically reconfigured to add or remove CPUs, RAM, or I/O devices without requiring a reboot.
Before start configuring our first Oracle VM for SPARC let us understand types of ldoms, ldom services and virtual devices.
Types of logical domains
| Name | Purpose |
|---|---|
| Guest | No direct access to underlying hardware and does not provide virtual device or services to other ldoms. Uses virtual device. |
| I/O | has direct access to underlying hardware in the server. It can be used in cases like oracle DB which wants direct/raw access to the storage devices. |
| Service | provides virtualized devices and services to guest domains. |
| Control | Service domain that also runs the ldoms manager software to control the configuration of hypervisor. This ldom manager is responsible for mapping between physical and virtual devices. |
Virtual Services and Devices
| Abbreviation | Name | Purpose |
|---|---|---|
| VLDC | virtual logical domain channel | communication channel between logical domain and hypervisor |
| VCC | Virtual console concentrator | Acts as a virtual console for each logical domain |
| VSW | Virtual switch service | provides network access for guest ldoms to the physical network ports |
| VDS | virtual disk service | provides virtual storage service for guest ldoms |
| VCPU | virtual CPU | Each thread of a T series CPU acts as a virtual CPU |
| MAU | Mathematical arithmetic unit | Each core of T series CPU will have a MAU for accelerated RAS/DSA encryption |
| Memory | Physical memory is mapped into virtual memory and assigned to ldoms | |
| VCONS | Virtual console | a port in guest ldom that connects to the VCC service in control domain |
| VNET | Virtual network | network port in guest ldom which is connected to the VSW service in the control domain |
| VSDEV | Virtual disk service device | physical storage device that is virtualized by VDS service in control domain |
| VDISK | Virtual disk | VDISK in guest domain is connected to the VDS service in control domain/service domain |
Installing the OVM software
To install the LDOM software simply unzip the software zip and run the install-ldm script with -s option in case you don't want to use the configuration assistant to configure the primary and guest ldoms.
primary# unzip OVM_Server_SPARC_latest.zip primary# ./install-ldm -s
Creating the default services
Create the essential services like vsw, vcc and vds required to serve the guest LDOMs.
primary# ldm add-vcc port-range=5000-5100 primary-vcc0 primary
primary# ldm add-vds primary-vds0 primary
primary# ldm add-vsw net-dev=nxge0 primary-vsw0 primary
primary# ldm list-services primary
VDS
NAME VOLUME OPTIONS DEVICE
primary-vds0
VCC
NAME PORT-RANGE
primary-vcc0 5000-5100
VSW
NAME MAC NET-DEV DEVICE MODE
primary-vsw0 02:04:4f:fb:9f:0d nxge0 switch@0 prog,promisc
Initial configuration of the control domain
By default all the VCPUs, Memory and MAUs are assigned to the primary domain which is the default domain created after installing the OVM for SPARC software. Primary or control domain is used to configure all the guest ldoms and provide necessary virtual services to them like vcc, vsw and vds. Logical domain manager is responsible to create, delete, modify and control ldoms, thus make sure the ldmd service is running before configuring the primary and guest domains. Use delayed reconfiguration in order to configure the primary ldom without rebooting for previous changes to take effect.
primary# svcs -a | grep ldmd online 14:23:34 svc:/ldoms/ldmd:default primary# ldm set-mau 1 primary primary# ldm set-vcpu 8 primary primary# ldm start-reconf primary primary# ldm set-memory 4G primary primary# ldm add-config new_config primary# ldm list-config factory-default new_config [current]
Reboot the primary domain for configuration settings to take effect
primary# shutdown -y -g0 -i6
Enable networking between primary and guest domains
By default communication between control domain and all the guest domains is disabled. To enable it, virtual switch has to be configured as the network device instead of nxge0.
primary# ifconfig nxge0 down unplumb primary# ifconfig vsw0 plumb primary# ifconfig vsw0 192.168.1.2 netmask + broadcast + up primary# mv /etc/hostname.nxge0 /etc/hostname.vsw0
Enable virtual network terminal server daemon
The vntsd daemon is responsible to provide the virtual network terminal services to the guest ldoms. If this service is not running enable it with svcadm command.
primary# svcadm enable vntsd
primary# svcs vntsd
STATE STIME FMRI
online Oct_12 svc:/ldoms/vntsd:default
Setting up the Guest Domain
We would assign 8 VCPUs, 2 GB of memory and 1 MAU to our first guest ldom. Also a virtual network vnet1 will be created and associated with the virtual switch vsw0.
primary# ldm add-domain ldom01 primary# ldm add-vcpu 8 ldom01 primary# ldm add-memory 2G ldom01 primary# ldm set-mau 1 ldom01 primary# ldm add-vnet vnet1 primary-vsw0 ldom01
Adding storage to the guest domain
Here we first need to specify the physical device that needs to be exported by vdsdev to the guest domain and then we actually add the virtual disk thus created to the guest domain. Now use any one of the 3 methods mentioned below.
- Adding physical disks
primary# ldm add-vdsdev /dev/dsk/c2t1d0s2 vol1@primary-vds0 primary# ldm add-vdisk vdisk1 vol1@primary-vds0 ldom01
- Adding file
primary# mkfile 10g /ldoms/ldom01_boot primary# ldm add-vdsdev /ldoms/ldom01_boot vol1@primary-vds0 primary# ldm add-vdisk vdisk1 vol1@primary-vds0 ldom01
- Adding a volume
primary# zfs create -V 5gb pool/vol01 primary# ldm add-vdsdev /dev/zvol/dsk/pool/vol01 vol1@primary-vds0 primary# ldm add-vdisk vdisk1 vol1@primary-vds0 ldom01
Setting variables
Setup the boot environment variable for the guest ldom.
primary# ldm set-var auto-boot?=true ldom01 primary# ldm set-var boot-device=vdisk1 ldom01
Setting up the solaris ISO image for installing guest ldom
Now we can also do a jumpstart installation of the guest domain. But one of the easiest and most widely used method is add iso image as virtual disk to the guest ldom and install it from it. Here you can access the vdisk sol10_iso in the ok prompt and boot from it.
primary# ldm add-vdsdev options=ro /data/sol_10.iso iso@primary-vds0 primary# ldm add-vdisk sol10_iso iso@primary-vds0 ldom01
Bind and start installing the ldom
primary# ldm bind ldom01 primary# ldm start ldom01 LDom ldom01 started ok> devalias ok> boot sol10_iso
Connect the guest domain
Now check the port which is bound with the guest domain and connect the virtual console of the guest domain.
primary# ldm list NAME STATE FLAGS CONS VCPU MEMORY UTIL UPTIME primary active -n-cv SP 8 4G 0.3% 8h 46m ldom01 active -n--- 5000 8 2G 48% 1h 52m
Flag definitions
Now you can see various flags in the ldm list command output. The flags represent the current state of the ldom.
| Column | flag | State |
|---|---|---|
| 1 | s | starting or stopping |
| 2 | n | normal |
| t | transition | |
| 3 | d | delayed reconfiguration |
| 4 | c | control domain |
| 5 | v | virtual I/O service domain |
| 6 | s | source domain in migration |
| t | target domain in migration | |
| e | error occurred in migration |
primary# telnet localhost 5000
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Connecting to console "ldom01" in group "ldom01" .... Press ~? for control options ..
Other useful commands
View current version of Oracle VM server for SPARC software
primary# ldm -V
Long listing of domains
primary# ldm list -l
List the resource for all LDOMs and per LDOM
primary# ldm list -o cpu primary# ldm list -o network,memory ldom01
List the boot variables
primary# ldm list-variable boot-device ldg1 boot-device=/virtual-devices@100/channel-devices@200/disk@0:a
List the bindings of all the LDOMs
primary# ldm list-bindings ldom
List all server resources, bound and unbound
primary# ldm list-devices -a primary# ldm list-devices mem