NAME¶
Smokeping::probes::basefork - Yet Another Base Class for implementing SmokePing
Probes
OVERVIEW¶
Like Smokeping::probes::basevars, but supports the probe-specific property
`forks' to determine how many processes should be run concurrently. The
targets are pinged one at a time, and the number of pings sent can vary
between targets.
SYNOPSIS¶
*** Probes ***
+basefork
forks = 5
offset = 50%
step = 300
timeout = 15
# The following variables can be overridden in each target section
pings = 5
# [...]
*** Targets ***
probe = basefork # if this should be the default probe
# [...]
+ mytarget
# probe = basefork # if the default probe is something else
host = my.host
pings = 5
DESCRIPTION¶
Not all pinger programs support testing multiple hosts in a single go like
fping(1). If the measurement takes long enough, there may be not enough
time perform all the tests in the time available. For example, if the test
takes 30 seconds, measuring ten hosts already fills up the SmokePing default
five minute step.
Thus, it may be necessary to do some of the tests concurrently. This module
defines the
ping method that forks the requested number of concurrent
processes and calls the
pingone method that derived classes must
provide.
The
pingone method is called with one argument: a hash containing the
target that is to be measured. The contents of the hash are described in
Smokeping::probes::basevars(3pm).
The number of concurrent processes is determined by the probe-specific variable
`forks' and is 5 by default. If there are more targets than this value,
another round of forks is done after the first processes are finished. This
continues until all the targets have been tested.
The timeout in which each child has to finish is set to 5 seconds multiplied by
the maximum number of 'pings' of the targets. You can set the base timeout
differently if you want to, using the timeout property of the probe in the
master config file (this again will be multiplied by the maximum number of
pings). The probe itself can also provide another default value if desired by
modifying the _default value of the timeout variable.
If the child isn't finished when the timeout occurs, it will be killed along
with any processes it has started.
The number of pings sent can be specified in the target-specific variable
'pings'.
VARIABLES¶
Supported probe-specific variables:
- forks
- Run this many concurrent processes at maximum
Example value: 5
Default value: 5
- offset
- If you run many probes concurrently you may want to prevent them from
hitting your network all at the same time. Using the probe-specific offset
parameter you can change the point in time when each probe will be run.
Offset is specified in % of total interval, or alternatively as 'random',
and the offset from the 'General' section is used if nothing is specified
here. Note that this does NOT influence the rrds itself, it is just a
matter of when data acqusition is initiated. (This variable is only
applicable if the variable 'concurrentprobes' is set in the 'General'
section.)
Example value: 50%
- step
- Duration of the base interval that this probe should use, if different
from the one specified in the 'Database' section. Note that the step in
the RRD files is fixed when they are originally generated, and if you
change the step parameter afterwards, you'll have to delete the old RRD
files or somehow convert them. (This variable is only applicable if the
variable 'concurrentprobes' is set in the 'General' section.)
Example value: 300
- timeout
- How long a single 'ping' takes at maximum
Example value: 15
Default value: 5
Supported target-specific variables:
- pings
- How many pings should be sent to each target, if different from the global
value specified in the Database section. Note that the number of pings in
the RRD files is fixed when they are originally generated, and if you
change this parameter afterwards, you'll have to delete the old RRD files
or somehow convert them.
Example value: 5
AUTHORS¶
Niko Tyni <ntyni@iki.fi>
SEE ALSO¶
Smokeping::probes::basevars, Smokeping::probes::EchoPing