Ubuntu Manpage: munin.conf - Munin configuration file

NAME

       munin.conf - Munin configuration file

DESCRIPTION

Munin is a group of programs to gather data from hosts, graph them, create html-pages, and optionally
warn contacts about any off-limit values.

The hosts are divided into three groups: One master (could be more, but Munin is not cluster aware so
they'll likely be independent). The master contacts a number of machines running munin-node, these are
called nodes. Each node has data from one or more hosts that is monitored by Munin.

munin.conf is the configuration file for the Munin master server. The programs using it are munin-
update, munin-graph, munin-limits and munin-html. There is also quite extensive documentation of this
file at <http://munin-monitoring.org/wiki/munin.conf>

The format of the file is simple. A minimal configuration looks something like:

[machine1.your.dom]
address localhost

The default location of munin.conf is /etc/munin/munin.conf. If your placement deviates from this norm,
use the "--config <file>"-option when running the munin-* programs.

Munin-update will expand all node-entries in this file, and save them to /var/lib/munin/datafile, which
is used by all programs in the package together with this file.

Any directives in this file will override directives of the same name in datafile. E.g., if you want to
change the title of the "load"-graph in the above minimum configuration, you would modify the two bottom
lines to:

[machine1.your.dom]
address localhost
load.graph_title Edited title of the load-graph

This will override the "graph_title" attribute of the "load" field/data series while keeping all the
others at their default.

GLOBAL DIRECTIVES

These directives should appear in munin.conf before any host or group definitions.

dbdir path (Default: /var/lib/munin)
Directory for generated database files. Required.

logdir path (Default: /var/log/munin)
Directory for log files. Required.

htmldir path (Default: /var/cache/munin/www)
Directory for HTML pages and graphs. Required.

rundir path (Default: /var/run/munin)
Directory for files tracking munin's current running state. Required.

tmpldir path (Default: /etc/munin/templates)
Directory for templates used to generate HTML pages. Required.

fork value
This directive determines whether munin-update fork when gathering information from nodes. Possible
values are "yes" and "no". Default is "yes". If you set it to "no" munin-update will collect data
from the nodes in sequence rather than in parallel and this will take considerably more time.
Affects: munin-update.

palette default|old
Choose palette between the very nice ""default"", and the good old ""old"".

graph_data_size value
This directive sets the resolution of the RRD files that are created. Possible values are "normal"
and "huge". Default is "normal". "Huge" is really huge, it saves the complete data with 5 minute
resolution for 400 days. This will probably increase the I/O load on your Munin master, and
currently has very little benefit. Affects: munin-update.

graph_strategy value
Deprecated. (Graphs are now always drawn via CGI.)

local_address value
The local address to connect any node from in case the master has several IP interfaces. This can be
overridden by a group or global directive. Without this directive Munins traffic will originate from
the master server according to the IP routing table.

max_processes <value>
This directive specifies the maximum number of processes to be used for gathering information from
nodes. If left blank, munin will use as many processes as necessary. Affects: munin-update.

max_graph_jobs <value>
This directive specifies the maximum number of concurrent rrdgraph proesses started by munin-graph.
The default is 6. A setting of 0 disables concurrent processing. Affects: munin-graph

max_cgi_graph_jobs <value>
This directive specifies the maximum number of concurrent munin-cgi-graph jobs. The web server can
start a high number of munin-cgi-graph jobs which we can't stop, but munin-cgi-graph will throttle
down how many rrdgraph calls will be running at the same time to this number. Affects: munin-cgi-
graph and munin-fastcgi-graph.

timeout_fetch_all_nodes seconds
This directive will set the maximum amount of time in seconds the munin-update task may run. So we'll
make sure the update ended within the 5 minutes timespan needed to have complete graphs without gaps.

You should probably not increase this value, unless all nodes are using ssh with munin-async.
Otherwise you may expecience gaps in graphs, if "munin-update" takes longer, than the default period
(5 minutes).

Munin-async can retrieve historical data, and if there is a big backlog, we could need more time
depending on the size of the data generated by the plugin and the size of the backlog. This would
also mean that we wouldn't care to skip an update. So munin-async will get more time to retrieve the
backlog data. Afterwards new data will incrementally be fetched. Default is 240. Affects: munin-
update

timeout_fetch_one_node seconds
This directive will set the maximum amount of time in seconds the munin-update task may run for a
single node. This value can't be bigger than "timeout_fetch_all_nodes". Default is 180. Affects:
munin-update

ssh_command value
The name of the secure shell command to use. Can be fully qualified, or looked up in $PATH.
Default: "ssh"

ssh_options value
The "ssh" command line options. Defaults: "-o ChallengeResponseAuthentication=no -o
StrictHostKeyChecking=no".

If you need per-host ssh configuration, add these to ~/munin/.ssh/config

tls <value>
Can have four values. "paranoid", "enabled", "auto", and "disabled". "Paranoid" and "enabled"
require a TLS connection, while "disabled" will not attempt one at all.

The current default is "disabled" because "auto" is broken. "Auto" causes bad interaction between
munin-update and munin-node if the node is unprepared to go to TLS.

If you see data dropouts (gaps in graphs) please try to disable TLS. Affects: munin-update.

tls_verify_certificate <value>
This directive can be "yes" or "no". It determines if the remote certificate needs to be signed by a
CA that is known locally. Default is "no". Affects: munin-update.

tls_private_key <value>
This directive sets the location of the private key to be used for TLS. Default is
/etc/munin/munin.pem. The private key and certificate can be stored in the same file. Affects:
munin-update.

tls_certificate <value>
This directive sets the location of the TLS certificate to be used for TLS. Default is
/etc/munin/munin.pem. The private key and certificate can be stored in the same file. Affects:
munin-update.

tls_ca_certificate <value>
This directive sets the CA certificate to be used to verify the node's certificate, if
tls_verify_certificate is set to "yes". Default is /etc/munin/cacert.pem. Affects: munin-update.

tls_verify_depth <value>
This directive sets how many signings up a chain of signatures TLS is willing to go to reach a known,
trusted CA when verifying a certificate. Default is 5. Affects: munin-update.

tls_match <value>
This directive, if defined, searches a dump of the certificate provided by the remote host for the
given regex. The dump of the certificate is two lines of the form:

Subject Name: /C=c/ST=st/L=l/O=o/OU=ou/CN=cn/emailAddress=email
Issuer Name: /C=c/ST=st/O=o/OU=ou/CN=cn/emailAddress=email

So, for example, one could match the subject distinguished name by the directive:

tls_match Subject Name: /C=c/ST=st/L=l/O=o/OU=ou/CN=cn/emailAddress=email

Note that the fields are dumped in the order they appear in the certificate. It's best to view the
dump of the certificate by running munin-update in debug mode and reviewing the logs.

Unfortunately, due to the limited functionality of the SSL module in use, it is not possible to
provide finer-grained filtering. By default this value is not defined. Affects: munin-update.

FIXME: This section MAY be complete, it may be missing a directive or two.

HOST DEFINITIONS

Host definitions can have several types. In all forms, the definition is used to generate the host name
and group for the host, and the following lines define its directives. All following directives apply to
that node until another node definition or EOF. Note that when defining a nodename it is vital that you
use a standard DNS name, as in, one that uses only a-z, '-', and '.'. While other characters can be used
in a DNS name, it is against the RFC, and Munin uses the other characters as delimiters. If they appear
in nodenames, unexpected behavior may occur.

The simplest node definition defines the section for a new node by simply wrapping the DNS name of the
node in brackets, e.g. "[machine1.your.dom]". This will add the node "machine1.your.dom" to the group
"your.dom".

The next form of definition is used to define the node and group independently. It follows the form
"[your.dom;machine1.sub.your.dom]". This adds the node "machine1.sub.your.dom" to the group "your.dom".
This can be useful if you have machines you want to put together as a group that are under different
domains (as in the given example). This can also solve a problem if your machine is "machine1.com",
where having a group of "com" makes little sense.

Multiple groups can be specified by adding more "groupname;"s, e.g. "[servers;local;mail;mail.foo.net]",
if you need a more hierarchical structure.

NODE DIRECTIVES

       These are directives that can follow a node definition and will apply only to that node.

       address <value>
           The IP address of the node.  Required.

       local_address <value>
           The local address to connect to the node from.  This overrides a group or global directive.

       FIXME: This section is incomplete.

PLUGIN DIRECTIVES

       These  directives  should  appear after a node definition and are of the form "plugin.directive <value>".
       Using these directives you can override various directives for a plugin, such as its  contacts,  and  can
       also be used to create graphs containing data from other plugins.

       FIXME: This section is (obviously) incomplete.

FIELD DIRECTIVES

       These directives should appear after a node definition and are of the form "plugin.field <value>".  Using
       these  directives  you  can  override  values originally set by plugins on the nodes, such as warning and
       critical levels or graph names.

       graph_height <value>
           The graph height for a specific service.  Default is 175.  Affects: munin-graph.

       graph_width <value>
           The graph width for a specific service.  Default is 400.  Affects: munin-graph.

       warning <value>
           The value at which munin-limits will mark the service as being in a warning state.  Value  can  be  a
           single number to specify a limit that must be passed or they can be a comma separated pair of numbers
           defining a valid range of values.  Affects: munin-limits.

       critical <value>
           The  value  at which munin-limits will mark the service as being in a critical state.  Value can be a
           single number to specify a limit that must be passed or they can be a comma separated pair of numbers
           defining a valid range of values Affects: munin-limits.

       FIXME: This section is incomplete.

EXAMPLES

       On all the examples below, all the 'top-level' parameters  (dbdir,  logdir,  htmldir,  tmpldir)  are  not
       present. They are only skipped for brevity - they are needed.

EXAMPLE 1

       An example with three servers on two domains:

               [machine1.one.dom]
                       address machine1.one.dom

               [machine2.one.dom]
                       address 10.33.32.123

               [machine3.two.dom]
                       address localhost

       This will appear as two groups (one.dom and two.dom), having respectively two and one node.

EXAMPLE 2

       Summarize the 'load'-graphs of the two servers in one.dom, in a 'total load'-graph.

               [one.dom;Totals]
                       update no
                       load.graph_title Total load
                       load.sum_load.label load
                       load.sum_load.special_stack machine1=machine1.one.dom:load.load machine2=machine2.one.dom:load.load

AUTHORS

       Jimmy Olsen, Audun Ytterdal, Brian de Wolf, Nicolai Langfeldt

COPYRIGHT

       Copyright (C) 2002-2008 Audun Ytterdal, Jimmy Olsen, Nicolai Langfeldt, Linpro AS and others.

       This  is  free  software;  see  the  source  for  copying  conditions. There is NO warranty; not even for
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

       This program is released under the GNU General Public License