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Diffstat (limited to 'src/varnish-mib.8')
-rw-r--r-- | src/varnish-mib.8 | 85 |
1 files changed, 57 insertions, 28 deletions
diff --git a/src/varnish-mib.8 b/src/varnish-mib.8 index 8d86f18..77912af 100644 --- a/src/varnish-mib.8 +++ b/src/varnish-mib.8 @@ -1,108 +1,136 @@ .\" This file is part of Varnish-mib -*- nroff -*- -.\" Copyright (C) 2014-2016 Sergey Poznyakoff +.\" Copyright (C) 2014-2018 Sergey Poznyakoff .\" .\" Varnish-mib is free software; you can redistribute it and/or modify .\" it under the terms of the GNU General Public License as published by .\" the Free Software Foundation; either version 3, or (at your option) .\" any later version. .\" .\" Varnish-mib is distributed in the hope that it will be useful, .\" but WITHOUT ANY WARRANTY; without even the implied warranty of .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the .\" GNU General Public License for more details. .\" .\" You should have received a copy of the GNU General Public License .\" along with Varnish-mib. If not, see <http://www.gnu.org/licenses/>. -.TH VARNISH-MIB 8 "February 2, 2018" "varnish-mib" +.TH VARNISH-MIB 8 "February 5, 2018" "varnish-mib" .SH NAME -varnish\-mib \- net-snmp module for obtaining Varnish Cache statistics +varnish\-mib \- Net-SNMP module for Varnish Cache monitoring .SH SYNOPSIS In \fBsnmpd.conf\fR(5): .PP .B dlmod varnish_mib /usr/lib/snmp/varnish\-mib.so .SH DESCRIPTION Dynamically loadable object module for .B net-snmp that provides access to Varnish Cache statistics. The module is loaded into .BR snmpd (8) as shown above (actual path can of course differ, depending on how -the package was configured). The module is written for Varnish -version \fB5.\fIX\fR. +the package was configured). This version is written for Varnish +\fB5.2.0\fR. .PP -The module obtains most of the data using Varnish API, and \fBvarnishd\fR -administrative interface. You should make sure that \fBsnmpd\fR is -able to access both data sources. +The values in the OID branches +.BR client , +.BR total , +.BR master , +.BR session , +.BR threads ", and " +.B objects +are obtained from Varnish API. .PP -The user \fBsnmpd\fR runs as should be able to read contents of the -\fB/var/lib/varnish/\fIHOSTNAME\fB/_.vsm_mgt\fR directory and read -files located in it. It must also have read permission on the varnish -secret file. +The OID branches +.BR backend , +.BR bans ", and " +.B vcl +are obtained using \fBvarnishd\fR administrative interface (similar +to +.BR varnishadm (8)). +.PP +To retrieve this information, the module must +have enough permissions to scan the Varnish management directory and +read files located in it. This directory is normally named +\fB/var/lib/varnish/\fIHOSTNAME\fB/_.vsm_mgt\fR, where \fIHOSTNAME\fR +stands for the server's hostname. Unless +.BR snmpd (8) +is run as root, special measures should be undertaken in order to +grant access rights. For example, if the daemon runs as user +\fBsnmp\fR, running the following two commands after starting +\fBvarnishd\fR will do the trick: + +.EX + setfacl -m u:snmp:rx /var/lib/varnish/$(hostname)/_.vsm_mgt + setfacl -m u:snmp:r /var/lib/varnish/$(hostname)/_.vsm_mgt/* +.EE +.PP + .SH CONFIGURATION OPTIONS Configuration statements specific to .B varnish\-mib must appear in the .B snmpd.conf -file below the +file, after the .B dlmod statement that loads the module. .PP The following configuration statements are available: .TP \fBvarnishBanTableTimeout\fR \fINUMBER\fR To create \fBbanTable\fR (see below), \fBvarnish_mib\fR connects to \fBvarnish\fR administration port and issues the \fBban.list\fR command. To minimize the performance impact, the information obtained is cached for a predefined amount of time (60 seconds by default). This amount (in seconds) is configured by \fBvarnishBanTableTimeout\fR statement. .TP \fBvarnishBackendTableTimeout\fR \fINUMBER\fR Update interval for \fBbackendTable\fR. Default is 5 seconds. .TP \fBvarnishCLIPortTimeout\fR \fINUMBER\fR Sets timeout for I/O operations with Varnish administrative port. Default is 5 seconds. .PP -The following two statements are not normally needed, since -\fBvarnish-mib\fR obtains this information automatically. +The following two statements are not normally needed, but are +provided for completeness sake: .TP \fBvarnishCLISocket\fR \fIADDRESS\fR[:\fIPORT\fR] Sets the address of Varnish administrative interface socket. .TP \fBvarnishCLISecretFile\fR \fIFILE\fR -Pathname of the Varnish secret file. +Sets the pathname of the Varnish secret file. .SH DEBUGGING The module defines the following debugging tokens: .TP .B varnish_mib -General debugging information. +Produces general debugging information. .TP .B varnish_mib:ban -Debug ban table loading. +Outputs verbose report about loading th ban table. .TP .B varnish_mib:vcli -Varnish +Displays additional information regarding varnish .B CLI interaction. .TP .B varnish_mib:vcli:transcript -Enables full transcript of CLI interaction. +Enables full transcript of varnish CLI session. .TP .B varnish_mib:backend -Debug loading the backend information. +Outputs verbose information about loading the backend information. .SH OIDS -The following OIDs are defined: +The following OIDs are defined in the +.B VARNISH-MIB.txt +file: .SS Branch \(dqclient\(dq .TP .B clientAcceptedConnections Number of accepted connections. .TP .B clientRequestsReceived Number of received HTTP requests. .TP .B clientCacheHits Number of cache hits. A cache hit indicates that an object has been delivered to a client without fetching it from a backend server. .TP @@ -113,27 +141,27 @@ passes the request to the backend and this decision itself has been cached. .B clientCacheMisses Number of misses. A cache miss indicates the object was fetched from the backend before delivering it to the client. .TP .B clientRequests400 Client requests received, subject to 400 errors. .TP .B clientBan A write-only OID. When set, invalidates the cache using the supplied value as argument to ban. When read, returns an empty string. E.g., to invalidate caches of all \fBpng\fR images: -.EE -snmpset \fBhostname\fR VARNISH\-MIB::clientBan.0 s 'req.url ~ \(dq\\.png$\(dq' .EX +snmpset \fIhostname\fR VARNISH\-MIB::clientBan.0 s 'req.url ~ \(dq\\.png$\(dq' +.EE .SS Branch \(dqbackend\(dq .TP .B backendConnSuccess Number of successful connections to the backend. .TP .B backendConnNotAttempted Number of backend connections not attempted, because of the unhealthy status of the backend. .TP .B backendConnToMany Number of backend connections failed because there were too many connections open. @@ -249,41 +277,42 @@ Master daemon uptime, in hundredths of a second. Number of sessions succesfully accepted. .TP .B sessQueued Number of times session was queued waiting for a thread. .TP .B sessDropped Number of sessions dropped because session queue was full. .TP .B sessClosed Number of sessions closed. .TP .B sessPipeline -Session pipeline. This variable is available only in Varnish version \fR4.0\fR. +This OID was used in Varnish \fR4.1\fR, but disappeared from version +\fB5.0\fR. .TP .B sessReadAhead Session read-ahead. .TP .B sessHerd Session herd. .TP .B sessDrop Number of sessions dropped for thread. .TP .B sessFail Number of session accept failures. .TP .B sessPipeOverflow -Number of session pipe overflows. This variable is available only in -Varnish version \fR4.0\fR. +This OID was used in Varnish \fR4.1\fR, but disappeared in version +\fB5.0\fR. .SS Branch \(dqthreads\(dq .TP .B threadsPools Number of thread pools. .TP .B threadsTotal Number of thread pools. .TP .B threadsLimitHits Number of times more threads were needed, but limit was reached in a thread pool. .TP @@ -358,25 +387,25 @@ Number of references to that ban. This equals to the number of objects in the varnish cache affected by that ban. .TP .B banExpression VCL expression of the ban. .RE Notice that for performance reasons, the ban table is cached, so the total number of rows in the \fBbanTable\fR may diverge from the value of \fBbansTotal\fR variable. The default update interval is 60 seconds. It can be configured in the \fBsnmpd.conf\fR file (see the \fBvarnishBanTableTimeout\fR statement above). .SS Branch \(dqagent\(dq -The \fBagent\fR branch is reserved for OIDs for +The \fBagent\fR branch is reserved for implementation-specific management. It is not used currently. .SH NOTES The following OIDs were used in Varnish 4. They are no longer available in Varnish 5: .TP .B clientRequests411 Client requests received, subject to 411 errors. This variable is available only in Varnish version \fR4.0\fR. .TP .B clientRequests413 Client requests received, subject to 413 errors. This variable is available only in Varnish version \fR4.0\fR. |