Skip to main content

HAProxy Web API

Connector dependencies​

The following monitoring connectors will be installed when you install the HAProxy Web connector through the Configuration > Monitoring Connector Manager menu:

Pack assets​

This connector allows you to monitor HAProxy (including OSS/free versions) using the HAProxy ‘stats’ page. It only supports the json format, the csv format is not compatible.

Templates​

The Monitoring Connector HAProxy Web brings a host template:

  • App-Haproxy-Web-custom

The connector brings the following service templates (sorted by the host template they are attached to):

This host template has no associated service by default. Use the service discovery rules to deploy your services.

Discovery rules​

Service discovery​

Rule nameDescription
App-Haproxy-Web-Backend-NameDiscover 'backends' and monitor them
App-Haproxy-Web-Frontend-NameDiscover 'frontends' and monitor them

More information about discovering services automatically is available on the dedicated page and in the following chapter.

Collected metrics & status​

Here is the list of services for this connector, detailing all metrics and statuses linked to each service.

NameUnit
backend-statusN/A
backends~backend.queue.current.countcount
backend-current-session-rateN/A
backend-max-session-rateN/A
backends~backend.sessions.current.countcount
backends~backend.sessions.total.countcount
backends~backend.traffic.in.bitpersecondb/s
backends~backend.traffic.out.bitpersecondb/s
backends~backend.requests.denied.countcount
backends~backend.responses.denied.countcount
backends~backend.connections.error.countcount
backends~backend.responses.error.countcount
server-statusN/A
server-statusN/A
backends~servers1#server.sessions.current.countcount
backends~servers2#server.sessions.current.countcount
server-current-session-rateN/A
server-current-session-rateN/A
server-max-session-rateN/A
server-max-session-rateN/A
backends~servers1#server.responses.denied.countcount
backends~servers2#server.responses.denied.countcount
backends~servers1#server.connections.error.countcount
backends~servers2#server.connections.error.countcount
backends~servers1#server.responses.error.countcount
backends~servers2#server.responses.error.countcount

Prerequisites​

To monitor HAProxy statistics via the API, you need to enable the statistics interface in HAProxy. In your haproxy.cfg configuration file, add or modify the following section:

listen stats
    bind *:8404
    stats enable
    stats uri /haproxy?stats
    stats auth username:password
    stats refresh 10s

bind *:8404: Exposes the statistics page on port 8404. stats uri /haproxy?stats: Defines the URL to access the statistics. stats auth username:password: Sets authentication (choose your own username/password). stats refresh 10s: Refreshes the statistics every 10 seconds (you can adjust this value as needed).

You can verify access to the API page (from a browser or using curl):

curl -u username:password http://IP_HAPROXY:8404/haproxy?stats

Installing the monitoring connector​

Pack​

  1. If the platform uses an online license, you can skip the package installation instruction below as it is not required to have the connector displayed within the Configuration > Monitoring Connector Manager menu. If the platform uses an offline license, install the package on the central server with the command corresponding to the operating system's package manager:
dnf install centreon-pack-applications-haproxy-web
  1. Whatever the license type (online or offline), install the HAProxy Web connector through the Configuration > Monitoring Connector Manager menu.

Plugin​

Since Centreon 22.04, you can benefit from the 'Automatic plugin installation' feature. When this feature is enabled, you can skip the installation part below.

You still have to manually install the plugin on the poller(s) when:

  • Automatic plugin installation is turned off
  • You want to run a discovery job from a poller that doesn't monitor any resource of this kind yet

More information in the Installing the plugin section.

Use the commands below according to your operating system's package manager:

dnf install centreon-plugin-Applications-Haproxy-Web

Using the monitoring connector​

Using a host template provided by the connector​

  1. Log into Centreon and add a new host through Configuration > Hosts.
  2. Fill in the Name, Alias & IP Address/DNS fields according to your resource's settings.
  3. Apply the App-Haproxy-Web-custom template to the host. A list of macros appears. Macros allow you to define how the connector will connect to the resource, and to customize the connector's behavior.
  4. Fill in the macros you want. Some macros are mandatory.
MacroDescriptionDefault valueMandatory
HAPROXYUSERNAMElogin
HAPROXYPASSWORDpassword
HAPROXYPROTOCOLhttp
HAPROXYPORT8404
  1. Deploy the configuration. The host appears in the list of hosts, and on the Resources Status page. The command that is sent by the connector is displayed in the details panel of the host: it shows the values of the macros.

Using a service template provided by the connector​

  1. If you have used a host template and checked Create Services linked to the Template too, the services linked to the template have been created automatically, using the corresponding service templates. Otherwise, create manually the services you want and apply a service template to them.
  2. Fill in the macros you want (e.g. to change the thresholds for the alerts). Some macros are mandatory (see the table below).
MacroDescriptionDefault valueMandatory
FILTERNAMEDefine which backends should be monitored based on their names. This option will be treated as a regular expression.*
WARNINGBACKENDCONNECTIONSERRORSThresholds
CRITICALBACKENDCONNECTIONSERRORSThresholds
WARNINGBACKENDCURRENTQUEUEThresholds
CRITICALBACKENDCURRENTQUEUEThresholds
WARNINGBACKENDCURRENTSESSIONRATEThresholds
CRITICALBACKENDCURRENTSESSIONRATEThresholds
WARNINGBACKENDCURRENTSESSIONSThresholds
CRITICALBACKENDCURRENTSESSIONSThresholds
WARNINGBACKENDDENIEDREQUESTSThresholds
CRITICALBACKENDDENIEDREQUESTSThresholds
WARNINGBACKENDDENIEDRESPONSESThresholds
CRITICALBACKENDDENIEDRESPONSESThresholds
WARNINGBACKENDMAXSESSIONRATEThresholds
CRITICALBACKENDMAXSESSIONRATEThresholds
WARNINGBACKENDRESPONSESERRORSThresholds
CRITICALBACKENDRESPONSESERRORSThresholds
WARNINGBACKENDSTATUSDefine the conditions to match for the backend status to be WARNING. You can use the following variables: %{status}. Example: C<--warning-backend-status='%{status} !~ /UP/i'>
CRITICALBACKENDSTATUSDefine the conditions to match for the backend status to be CRITICAL. Default: C<'%{status} !~ /UP/i'>. You can use the following variables: C<%{status}>. Example: C<--critical-backend-status='%{status} !~ /UP/i'>
WARNINGBACKENDTOTALSESSIONSThresholds
CRITICALBACKENDTOTALSESSIONSThresholds
WARNINGBACKENDTRAFFICINThresholds in b/s
CRITICALBACKENDTRAFFICINThresholds in b/s
WARNINGBACKENDTRAFFICOUTThresholds in b/s
CRITICALBACKENDTRAFFICOUTThresholds in b/s
WARNINGSERVERCONNECTIONSERRORSThresholds
CRITICALSERVERCONNECTIONSERRORSThresholds
WARNINGSERVERCURRENTSESSIONRATEThresholds
CRITICALSERVERCURRENTSESSIONRATEThresholds
WARNINGSERVERCURRENTSESSIONSThresholds
CRITICALSERVERCURRENTSESSIONSThresholds
WARNINGSERVERDENIEDRESPONSESThresholds
CRITICALSERVERDENIEDRESPONSESThresholds
WARNINGSERVERMAXSESSIONRATEThresholds
CRITICALSERVERMAXSESSIONRATEThresholds
WARNINGSERVERRESPONSESERRORSThresholds
CRITICALSERVERRESPONSESERRORSThresholds
WARNINGSERVERSTATUSDefine the conditions to match for the server status to be WARNING. You can use the following variables: C<%{status}>. Example: C<--warning-backend-status='%{status} !~ /UP/i'>
CRITICALSERVERSTATUSDefine the conditions to match for the status to be CRITICAL. Default: C<'%{status} !~ /UP/i'>. You can use the following variables: C<%{status}>. Example: C<--critical-backend-status='%{status} !~ /UP/i'>
EXTRAOPTIONSAny extra option you may want to add to the command (a --verbose flag for example). All options are listed here.--verbose
  1. Deploy the configuration. The service appears in the list of services, and on the Resources Status page. The command that is sent by the connector is displayed in the details panel of the service: it shows the values of the macros.

How to check in the CLI that the configuration is OK and what are the main options for?​

Once the plugin is installed, log into your Centreon poller's CLI using the centreon-engine user account (su - centreon-engine). Test that the connector is able to monitor a resource using a command like this one (replace the sample values by yours):

/usr/lib/centreon/plugins/centreon_haproxy_web.pl \
	--plugin=apps::haproxy::web::plugin  \
	--mode=backend-usage \
	--hostname='10.0.0.1' \
	--port='8404' \
	--proto='http' \
	--username='login' \
	--password='password'  \
	--filter-name='.*' \
	--warning-backend-status='' \
	--critical-backend-status='' \
	--warning-backend-current-queue='' \
	--critical-backend-current-queue='' \
	--warning-backend-current-session-rate='' \
	--critical-backend-current-session-rate='' \
	--warning-backend-max-session-rate='' \
	--critical-backend-max-session-rate='' \
	--warning-backend-current-sessions='' \
	--critical-backend-current-sessions='' \
	--warning-backend-total-sessions='' \
	--critical-backend-total-sessions='' \
	--warning-backend-traffic-in='' \
	--critical-backend-traffic-in='' \
	--warning-backend-traffic-out='' \
	--critical-backend-traffic-out='' \
	--warning-backend-denied-requests='' \
	--critical-backend-denied-requests='' \
	--warning-backend-denied-responses='' \
	--critical-backend-denied-responses='' \
	--warning-backend-connections-errors='' \
	--critical-backend-connections-errors='' \
	--warning-backend-responses-errors='' \
	--critical-backend-responses-errors='' \
	--warning-server-status='' \
	--critical-server-status='' \
	--warning-server-current-sessions='' \
	--critical-server-current-sessions='' \
	--warning-server-current-session-rate='' \
	--critical-server-current-session-rate='' \
	--warning-server-max-session-rate='' \
	--critical-server-max-session-rate='' \
	--warning-server-denied-responses='' \
	--critical-server-denied-responses='' \
	--warning-server-connections-errors='' \
	--critical-server-connections-errors='' \
	--warning-server-responses-errors='' \
	--critical-server-responses-errors='' \
	--verbose

The expected command output is shown below:

OK: current queue: 46578 current session rate: 39271/s max session rate: 2934/s current sessions: 17139 total sessions: 4481 traffic in: 79901 79901/s traffic out: 13701 13701/s denied requests: 11391 denied responses: 55189 connection errors: 63151 responses errors: 12544 Servers are ok | 'backends~backend.queue.current.count'=46578;;;0; 'backends~backend.session.current.rate.countpersecond'=39271;;;0; 'backends~backend.session.max.rate.countpersecond'=2934;;;0; 'backends~backend.sessions.current.count'=17139;;;0; 'backends~backend.sessions.total.count'=4481;;;0; 'backends~backend.traffic.in.bitpersecond'=79901b/s;;;0; 'backends~backend.traffic.out.bitpersecond'=13701b/s;;;0; 'backends~backend.requests.denied.count'=11391;;;0; 'backends~backend.responses.denied.count'=55189;;;0; 'backends~backend.connections.error.count'=63151;;;0; 'backends~backend.responses.error.count'=12544;;;0; 'backends~servers1#server.sessions.current.count'=85843;;;0; 'backends~servers2#server.sessions.current.count'=46527;;;0; 'backends~servers1#server.session.current.rate.countpersecond'=53920;;;0; 'backends~servers2#server.session.current.rate.countpersecond'=89626;;;0; 'backends~servers1#server.session.max.rate.countpersecond'=76902;;;0; 'backends~servers2#server.session.max.rate.countpersecond'=74257;;;0; 'backends~servers1#server.responses.denied.count'=30946;;;0; 'backends~servers2#server.responses.denied.count'=48861;;;0; 'backends~servers1#server.connections.error.count'=57703;;;0; 'backends~servers2#server.connections.error.count'=43456;;;0; 'backends~servers1#server.responses.error.count'=48057;;;0; 'backends~servers2#server.responses.error.count'=69566;;;0;

Troubleshooting​

Please find the troubleshooting documentation for Centreon Plugins typical issues.

Available modes​

In most cases, a mode corresponds to a service template. The mode appears in the execution command for the connector. In the Centreon interface, you don't need to specify a mode explicitly: its use is implied when you apply a service template. However, you will need to specify the correct mode for the template if you want to test the execution command for the connector in your terminal.

All available modes can be displayed by adding the --list-mode parameter to the command:

/usr/lib/centreon/plugins/centreon_haproxy_web.pl \
	--plugin=apps::haproxy::web::plugin  \
	--list-mode

The plugin brings the following modes:

ModeLinked service template
backend-usage [code]App-Haproxy-Web-Backend-Usage-custom
frontend-usage [code]App-Haproxy-Web-Frontend-Usage-custom
list-objects [code]Used for service discovery

Available options​

Generic options​

All generic options are listed here:

OptionDescription
--modeDefine the mode in which you want the plugin to be executed (see --list-mode).
--dyn-modeSpecify a mode with the module's path (advanced).
--list-modeList all available modes.
--mode-versionCheck minimal version of mode. If not, unknown error.
--versionReturn the version of the plugin.
--custommodeWhen a plugin offers several ways (CLI, library, etc.) to get information the desired one must be defined with this option.
--list-custommodeList all available custom modes.
--multipleMultiple custom mode objects. This may be required by some specific modes (advanced).
--pass-managerDefine the password manager you want to use. Supported managers are: environment, file, keepass, hashicorpvault and teampass.
--verboseDisplay extended status information (long output).
--debugDisplay debug messages.
--filter-perfdataFilter perfdata that match the regexp. Example: adding --filter-perfdata='avg' will remove all metrics that do not contain 'avg' from performance data.
--filter-perfdata-advFilter perfdata based on a "if" condition using the following variables: label, value, unit, warning, critical, min, max. Variables must be written either %{variable} or %(variable). Example: adding --filter-perfdata-adv='not (%(value) == 0 and %(max) eq "")' will remove all metrics whose value equals 0 and that don't have a maximum value.
--explode-perfdata-maxCreate a new metric for each metric that comes with a maximum limit. The new metric will be named identically with a '_max' suffix. Example: it will split 'used_prct'=26.93%;0:80;0:90;0;100 into 'used_prct'=26.93%;0:80;0:90;0;100 'used_prct_max'=100%;;;;
--change-perfdata --extend-perfdataChange or extend perfdata. Syntax: --extend-perfdata=searchlabel,newlabel,target[,[<new-unit-of-mesure>],[min],[max]] Common examples: =over 4 Convert storage free perfdata into used: --change-perfdata='free,used,invert()' Convert storage free perfdata into used: --change-perfdata='used,free,invert()' Scale traffic values automatically: --change-perfdata='traffic,,scale(auto)' Scale traffic values in Mbps: --change-perfdata='traffic_in,,scale(Mbps),mbps' Change traffic values in percent: --change-perfdata='traffic_in,,percent()' =back
--change-perfdataChange or extend perfdata. Syntax: --extend-perfdata=searchlabel,newlabel,target[,[<new-unit-of-mesure>],[min],[max]] Common examples: =over 4 Convert storage free perfdata into used: --change-perfdata='free,used,invert()' Convert storage free perfdata into used: --change-perfdata='used,free,invert()' Scale traffic values automatically: --change-perfdata='traffic,,scale(auto)' Scale traffic values in Mbps: --change-perfdata='traffic_in,,scale(Mbps),mbps' Change traffic values in percent: --change-perfdata='traffic_in,,percent()' =back
--extend-perfdataChange or extend perfdata. Syntax: --extend-perfdata=searchlabel,newlabel,target[,[<new-unit-of-mesure>],[min],[max]] Common examples: =over 4 Convert storage free perfdata into used: --change-perfdata='free,used,invert()' Convert storage free perfdata into used: --change-perfdata='used,free,invert()' Scale traffic values automatically: --change-perfdata='traffic,,scale(auto)' Scale traffic values in Mbps: --change-perfdata='traffic_in,,scale(Mbps),mbps' Change traffic values in percent: --change-perfdata='traffic_in,,percent()' =back
--extend-perfdata-groupAdd new aggregated metrics (min, max, average or sum) for groups of metrics defined by a regex match on the metrics' names. Syntax: --extend-perfdata-group=regex,<names-of-new-metrics>,calculation[,[<new-unit-of-mesure>],[min],[max]] regex: regular expression <names-of-new-metrics>: how the new metrics' names are composed (can use $1, $2... for groups defined by () in regex). calculation: how the values of the new metrics should be calculated <new-unit-of-mesure> (optional): unit of measure for the new metrics min (optional): lowest value the metrics can reach max (optional): highest value the metrics can reach Common examples: =over 4 Sum wrong packets from all interfaces (with interface need --units-errors=absolute): --extend-perfdata-group=',packets_wrong,sum(packets_(discard|error)_(in|out))' Sum traffic by interface: --extend-perfdata-group='traffic_in_(.*),traffic_$1,sum(traffic_(in|out)_$1)' =back
--change-short-output --change-long-outputModify the short/long output that is returned by the plugin. Syntax: --change-short-output=patternreplacementmodifier Most commonly used modifiers are i (case insensitive) and g (replace all occurrences). Example: adding --change-short-output='OKUpgi' will replace all occurrences of 'OK', 'ok', 'Ok' or 'oK' with 'Up'
--change-short-outputModify the short/long output that is returned by the plugin. Syntax: --change-short-output=patternreplacementmodifier Most commonly used modifiers are i (case insensitive) and g (replace all occurrences). Example: adding --change-short-output='OKUpgi' will replace all occurrences of 'OK', 'ok', 'Ok' or 'oK' with 'Up'
--change-long-outputModify the short/long output that is returned by the plugin. Syntax: --change-short-output=patternreplacementmodifier Most commonly used modifiers are i (case insensitive) and g (replace all occurrences). Example: adding --change-short-output='OKUpgi' will replace all occurrences of 'OK', 'ok', 'Ok' or 'oK' with 'Up'
--change-exitReplace an exit code with one of your choice. Example: adding --change-exit=unknown=critical will result in a CRITICAL state instead of an UNKNOWN state.
--change-output-advReplace short output and exit code based on a "if" condition using the following variables: short_output, exit_code. Variables must be written either %{variable} or %(variable). Example: adding --change-output-adv='%(short_ouput) =~ /UNKNOWN: No daemon/,OK: No daemon,OK' will change the following specific UNKNOWN result to an OK result.
--range-perfdataRewrite the ranges displayed in the perfdata. Accepted values: 0: nothing is changed. 1: if the lower value of the range is equal to 0, it is removed. 2: remove the thresholds from the perfdata.
--filter-uomMask the units when they don't match the given regular expression.
--opt-exitReplace the exit code in case of an execution error (i.e. wrong option provided, SSH connection refused, timeout, etc). Default: unknown.
--output-ignore-perfdataRemove all the metrics from the service. The service will still have a status and an output.
--output-ignore-labelRemove the status label ("OK:", "WARNING:", "UNKNOWN:", CRITICAL:") from the beginning of the output. Example: 'OK: Ram Total:...' will become 'Ram Total:...'
--output-xmlReturn the output in XML format (to send to an XML API).
--output-jsonReturn the output in JSON format (to send to a JSON API).
--output-openmetricsReturn the output in OpenMetrics format (to send to a tool expecting this format).
--output-fileWrite output in file (can be combined with JSON, XML and OpenMetrics options). Example: --output-file=/tmp/output.txt will write the output in /tmp/output.txt.
--disco-formatApplies only to modes beginning with 'list-'. Returns the list of available macros to configure a service discovery rule (formatted in XML).
--disco-showApplies only to modes beginning with 'list-'. Returns the list of discovered objects (formatted in XML) for service discovery.
--float-precisionDefine the float precision for thresholds (default: 8).
--source-encodingDefine the character encoding of the response sent by the monitored resource Default: 'UTF-8'. =head1 DESCRIPTION B<output>. =cut
--filter-countersOnly display some counters (regexp can be used). Example to check SSL connections only : --filter-counters='^xxxx|yyyy$'
--http-peer-addrSet the address you want to connect to. Useful if hostname is only a vhost, to avoid IP resolution.
--proxyurlProxy URL. Example: http://my.proxy:3128
--proxypacProxy pac file (can be a URL or a local file).
--insecureAccept insecure SSL connections.
--http-backendPerl library to use for HTTP transactions. Possible values are: lwp (default) and curl.
--hostnameIP address or FQDN of the HAProxy server.
--portPort used by the web server
--protoSpecify https if needed (default: 'http')
--urlpathDefine the path of the web page to get (default: '/stats;json;').
--credentialsSpecify this option if you are accessing a web page using authentication.
--usernameSpecify the username for authentication (mandatory if --credentials is specified).
--passwordSpecify the password for authentication (mandatory if --credentials is specified).
--basicSpecify this option if you are accessing a web page using basic authentication and don't want a '401 UNAUTHORIZED' error to be logged on your web server. Specify this option if you are accessing a web page using hidden basic authentication or you'll get a '404 NOT FOUND' error. (use with --credentials)
--ntlmv2Specify this option if you are accessing a web page using NTLMv2 authentication (use with C<--credentials> and C<--port> options).
--timeoutDefine the timeout in seconds (default: 5).

Modes options​

All available options for each service template are listed below:

OptionDescription
--add-serversAlso display and monitor Servers related to a given backend.
--filter-countersDefine which counters should appear in the performance data (metrics). This option will be treated as a regular expression. Example: C<--filter-counters='^total-connections$'>.
--filter-nameDefine which backends should be monitored based on their names. This option will be treated as a regular expression.
--warning-backend-statusDefine the conditions to match for the backend status to be WARNING. You can use the following variables: %{status}. Example: C<--warning-backend-status='%{status} !~ /UP/i'>
--critical-backend-statusDefine the conditions to match for the backend status to be CRITICAL. Default: C<'%{status} !~ /UP/i'>. You can use the following variables: C<%{status}>. Example: C<--critical-backend-status='%{status} !~ /UP/i'>
--warning-server-statusDefine the conditions to match for the server status to be WARNING. You can use the following variables: C<%{status}>. Example: C<--warning-backend-status='%{status} !~ /UP/i'>
--critical-server-statusDefine the conditions to match for the status to be CRITICAL. Default: C<'%{status} !~ /UP/i'>. You can use the following variables: C<%{status}>. Example: C<--critical-backend-status='%{status} !~ /UP/i'>
--warning-backend-current-queueThresholds.
--critical-backend-current-queueThresholds.
--warning-backend-current-session-rateThresholds.
--critical-backend-current-session-rateThresholds.
--warning-backend-max-session-rateThresholds.
--critical-backend-max-session-rateThresholds.
--warning-backend-current-sessionsThresholds.
--critical-backend-current-sessionsThresholds.
--warning-backend-total-sessionsThresholds.
--critical-backend-total-sessionsThresholds.
--warning-backend-traffic-inThresholds in b/s.
--critical-backend-traffic-inThresholds in b/s.
--warning-backend-traffic-outThresholds in b/s.
--critical-backend-traffic-outThresholds in b/s.
--warning-backend-denied-requestsThresholds.
--critical-backend-denied-requestsThresholds.
--warning-backend-denied-responsesThresholds.
--critical-backend-denied-responsesThresholds.
--warning-backend-connections-errorsThresholds.
--critical-backend-connections-errorsThresholds.
--warning-backend-responses-errorsThresholds.
--critical-backend-responses-errorsThresholds.
--warning-server-current-sessionsThresholds.
--critical-server-current-sessionsThresholds.
--warning-server-current-session-rateThresholds.
--critical-server-current-session-rateThresholds.
--warning-server-max-session-rateThresholds.
--critical-server-max-session-rateThresholds.
--warning-server-denied-responsesThresholds.
--critical-server-denied-responsesThresholds.
--warning-server-connections-errorsThresholds.
--critical-server-connections-errorsThresholds.
--warning-server-responses-errorsThresholds.
--critical-server-responses-errorsThresholds.

All available options for a given mode can be displayed by adding the --help parameter to the command:

/usr/lib/centreon/plugins/centreon_haproxy_web.pl \
	--plugin=apps::haproxy::web::plugin  \
	--mode=backend-usage \
	--help