gkrellmd(1): GNU Krell Monitors Server

NAME

gkrellmd - The GNU Krell Monitors Server

SYNOPSIS

gkrellmd Listens for connections from gkrellm clients. When a gkrellm client connects to a gkrellmd server all builtin monitors collect their data from the server. However, the gkrellm process is running on the local machine, so plugins enabled in gkrellm will collect data from the local context unless the plugin is client/server capable and has a gkrellmd plugin counterpart which is installed and enabled on the server. Enabling a gkrellmd plugin installed on a server requires adding a plugin-enable line to a gkrellmd.conf file.

Any command launching from a gkrellm client will run commands on the local machine. If you want to execute commands on the server, the client side commands will have to use sudo.

There is no support for file system mounting on the machine where the gkrellmd server is running.

OPTIONS

-h --help: Displays usage information and exits.
-v --version: Prints gkrellmd version and exits.
-V --verbose: Prints connection progress.
-u, --update-hz f: Sets the data update frequency in samples per second for the server. This is independent of and should be less than the gkrellm client update rate. The rate can be from 1 to 10 and should be lower to minimize network traffic. A value of not much more than 1/2 the client update rate is best where it is not important to minimize network traffic.
-m, --max-clients N: Sets the maximum number of simultaneous clients allowed to connect to the server.
-P, --port server_port: Use server_port for the network connection.
-a, --allow-host hostname: Specify hosts which are allowed to connect. Multiple allow-host arguments may be given. If no hosts are specified on the command line or in a gkrellmd.conf file, then all hosts are allowed to connect. The hostname argument may be a text name or a IPv4 or IPv6 dotted notation. For IPv4, the simple subnet pattern x.y.z.* may be used. Also, if hostname is the keyword ALL then all hosts are allowed. This option is additive and specified hosts will be added to the hostnames listed in gkrellmd.conf files unless the --clear-hosts option is given first.
-p, --plugin name: For plugin development convenience, load and enable the command line specified plugin to avoid repeated install steps in the development cycle. See the README from the gkrellm demo5 for more information on gkrellmd plugin development. Requires at least gkrellmd version 2.2.0.
-pe, --plugin-enable name: Specify an installed plugin to enable (this is probably more convenient to specify in a gkrellmd.conf file). Requires at least gkrellmd version 2.2.0.
-plist: Output a list of plugins which are installed and available to enable and exit. Requires at least gkrellmd version 2.2.0.
-plog: Output a log of the plugin install process. When requesting a log, the --detach option will have no effect. Requires at least gkrellmd version 2.2.0.
-c, --clear-hosts: Clears the current list of allowed hosts. Use this before any --allow-host arguments if you want command line allowed hosts to override and not be additive to those specified in gkrellmd.conf files.
-d, --detach: Runs gkrellmd in the background and detaches from the terminal.
-U, --user username: Changes user to username after startup. Useful if you want to run gkrellmd as root, but set it to run with another privileges; typically as the nobody user.
-G, --group groupname: Changes group to groupname after startup.
--inet-interval seconds: The Internet monitor defaults to reading TCP connections once per second. However, for Linux SMP kernels where reading /proc/net/tcp causes high cpu usage, the inet-interval may be set to 1-20 seconds to slow down /proc/net/tcp reads. Or set it to 0 to totally disable the Internet monitor. Requires at least gkrellmd version 2.1.8.
--io-timeout seconds: Configure gkrellm clients to disconnect from a gkrellmd server if there is an io-timeout interval where the client receives no input from the server. Use this for conditions where gkrellmd may be ungracefully terminated such that socket connections are not closed. Minimum is 2 (less than 2 for no I/O disconnecting and is the default). Requires at least 2.1.8 versions of both gkrellmd and gkrellm.
--reconnect-timeout seconds: Configure gkrellm clients to attempt automatic reconnects to a gkrellmd server every reconnect-timeout seconds after a disconnected state is detected. Disconnected states are created by normal gkrellmd shutdowns or by an expiring io-timeout. Minimum is 2 (less than 2 for no automatic reconnecting and is the default). Requires at least 2.1.8 versions of both gkrellmd and gkrellm.
--mailbox mbox_path: Check the server side mailbox mbox_path and send mail counts to connected gkrellm clients. Mailbox types may be mbox, Maildir, and MH mail. Requires at least 2.1.11 versions of both gkrellmd and gkrellm.
--net-timer net_interface: Configure gkrellmd to send the connect time for a network interface to all clients to be displayed in the client gkrellm timer button monitor display. If this is done, the client gkrellm timer button can still execute commands on the client, but the button will not affect the timer display. If you want the client timer button to execute commands on the server, your timer button commands will have to use sudo. So set this if your server box has say a ppp0 or ippp0 connection and you want to monitor its connect time. Requires at least 2.2.7 versions of both gkrellmd and gkrellm.

EXAMPLE

On the server machine where gkrellmd is installed, copy the sample gkrellmd.conf file from the server subdirectory of the gkrellm source tarball to one of the gkrellmd.conf locations listed in the FILES section and edit it to set your preferences or to enable plugins. Probably don't set the detached option until you are happy with the configuration. Run: gkrellmd

On a client machine, run: gkrellm -s server-machine-name

Configure the client gkrellm in its graphical configuration window as you wish, and that's all there is to it. Of course, if you don't use the default gkrellmd port number you will have to supply an appropriate port argument to the client gkrellm.

Available plugins will be installed in the plugins-gkrellmd directory locations listed in the FILES section. You may test enable any of these plugins with the -pe option, but for permanent enabling you should add a plugin-enable line to any gkrellmd.conf file listed in the FILES section. Run gkrellmd -plist to see a list of all installed plugins and run gkrellmd -plog to see a log of the plugin install process.