Chapter 16. Managing Virtual Machines Using xend

Chapter 16. Managing Virtual Machines Using xend

Chapter 16. Managing Virtual Machines Using xend

The xend node control daemon performs certain system management functions that relate to virtual machines. This daemon controls the virtualized resources, and xend must be running to interact with virtual machines. Before you start xend, you must specify the operating parameters by editing the xend configuration file xend-config.sxp which is located in the etc/xen directory. Here are the parameters you can enable or disable in the xend-config.sxp configuration file:

Item Description

console-limit

Determines the console server's memory buffer limit and assigns values on a per-domain basis

min-mem

Determines the minimum number of megabytes that is reserved for domain0 (if you enter 0, the value does not change)

dom0 cpus

Determines the number of CPUs in use by domain0 (at least 1 CPU is assigned by default)

enable-dump

Determines that a crash occurs then enables a dump (default is 0)

external-migration-tool

Determines the script or application that handles external device migration (scripts must reside in etc/xen/scripts/external-device-migrate

logfile

Determines the location of the log file (default is /var/log/xend.log)

loglevel

Filters out the log mode values: DEBUG, INFO, WARNING, ERROR, or CRITICAL (default is DEBUG)

network-script

Determines the script that enables the networking environment (scripts must reside in etc/xen/scripts directory)

xend-http-server

Enables the http stream packet management server (default is no)

xend-unix-server

Enables the unix domain socket server (a socket server is a communications endpoint that handles low level network connections and accepts or rejects incoming connections)

xend-relocation-server

Enables the relocation server for cross-machine migrations (default is no)

xend-unix-path

Determines the location where the xend-unix-server command outputs data (default is var/lib/xend/xend-socket)

xend-port

Determines the port that the http management server uses (default is 8000)

xend-relocation-port

Determines the port that the relocation serves uses (default is 8002)

xend-relocation-address

Determines the virtual machine addresses that are allowed for system migration

xend-address

Determines the address that the domain socket server binds to.

Table 16.1. Red Hat Virtualization xend Configuration Parameters

After setting these operating parameters, you should verify that xend is running and if not, initilize the daemon. At at the command prompt, you can start thexend daemon by entering the following:

service xend start

You can use xend to stop the daemon:

service xend stop

This stops the daemon from running.

You can use xend to restart the daemon:

service xend restart

The daemon starts once again.

You check the status of the xend daemon.

service xend status 

The output displays the daemon's status.