NAME
Smokeping::probes::Curl - a curl(1) probe for SmokePing
OVERVIEW
Fetches an HTTP or HTTPS URL using curl(1).
SYNOPSIS
*** Probes ***
+Curl
binary = /usr/bin/curl
forks = 5
offset = 50%
step = 300
# The following variables can be overridden in each target section
agent = User-Agent: Lynx/2.8.4rel.1 libwww-FM/2.14 SSL-MM/1.4.1 OpenSSL/0.9.6c
extraargs = -6 --head --user user:password
extrare = / /
follow_redirects = yes
include_redirects = yes
insecure_ssl = 1
interface = eth0
pings = 5
ssl2 = 1
timeout = 20
urlformat = http://%host%/ # mandatory
# [...]
*** Targets ***
probe = Curl # if this should be the default probe
# [...]
+ mytarget
# probe = Curl # if the default probe is something else
host = my.host
agent = User-Agent: Lynx/2.8.4rel.1 libwww-FM/2.14 SSL-MM/1.4.1 OpenSSL/0.9.6c
extraargs = -6 --head --user user:password
extrare = / /
follow_redirects = yes
include_redirects = yes
insecure_ssl = 1
interface = eth0
pings = 5
ssl2 = 1
timeout = 20
urlformat = http://%host%/ # mandatory
DESCRIPTION
(see curl(1) for details of the options below)
VARIABLES
Supported probe-specific variables:
binary
The location of your curl binary.
Default value: /usr/bin/curl
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
Supported target-specific variables:
agent
The "-A" curl(1) option. This is a full HTTP User-Agent header
including the words "User-Agent:". Note that it does not need any
quotes around it.
Example value: User-Agent: Lynx/2.8.4rel.1 libwww-FM/2.14
SSL-MM/1.4.1 OpenSSL/0.9.6c
extraargs
Any extra arguments you might want to hand to curl(1). The
arguments should be separated by the regexp specified in "extrare",
which contains just the space character (" ") by default.
Note that curl will be called with the resulting list of arguments
without any shell expansion. If you need to specify any arguments
containing spaces, you should set "extrare" to something else.
As a complicated example, to explicitly set the "Host:" header in
Curl requests, you need to set "extrare" to something else, eg.
"/;/", and then specify "extraargs = --header;Host:
www.example.com".
Example value: -6 --head --user user:password
extrare
The regexp used to split the extraargs string into an argument
list, in the "/regexp/" notation. This contains just the space
character (" ") by default, but if you need to specify any
arguments containing spaces, you can set this variable to a
different value.
Example value: / /
Default value: / /
follow_redirects
If this variable is set to ’yes’, curl will follow any HTTP
redirection steps (the ’-L’ option). If set to ’no’, HTTP
Location: headers will not be followed. See also
’include_redirects’.
Example value: yes
Default value: no
include_redirects
If this variable is set to ’yes’, the measurement result will
include the time spent on following any HTTP redirection steps. If
set to ’no’, only the last step is measured. See also
’follow_redirects’.
Example value: yes
Default value: no
insecure_ssl
The "-k" curl(1) option. Accept SSL connections that don’t have a
secure certificate chain to a trusted CA. Note that if you are
going to monitor https targets, you’ll probably have to either
enable this option or specify the CA path to curl through extraargs
below. For more info, see the curl(1) manual page.
Example value: 1
interface
The "--interface" curl(1) option. Bind to a specific interface, IP
address or host name.
Example value: eth0
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
ssl2
The "-2" curl(1) option. Force SSL2.
Example value: 1
timeout
The "-m" curl(1) option. Maximum timeout in seconds.
Example value: 20
Default value: 10
urlformat
The template of the URL to fetch. Can be any one that curl
supports. Any occurrence of the string ’%host%’ will be replaced
with the host to be probed.
Example value: http://%host%/
This setting is mandatory.
AUTHORS
Gerald Combs <gerald [AT] ethereal.com>
Niko Tyni <ntyni@iki.fi>
NOTES
You should consider setting a lower value for the "pings" variable than
the default 20, as repetitive URL fetching may be quite heavy on the
server.
The URL to be tested used to be specified by the variable ’url’ in
earlier versions of Smokeping, and the ’host’ setting did not influence
it in any way. The variable name has now been changed to ’urlformat’,
and it can (and in most cases should) contain a placeholder for the
’host’ variable.
SEE ALSO
curl(1), <http://curl.haxx.se/>