Apache 2 Bandwidth Quota and Throttling
Apache 2 Bandwidth Quota and Throttling
Documentation
Tutorials
- Manage Apache Download Speed And Traffic Limits With mod_cband - New!!
- mod_cband FAQ by Adam Dawidowski
- ISPConfig and BandWidth control (also in Spanish) by Erik Corona
Configuration
Configuration is very simple, you must write only several lines. First, you must add the following command to the main config file to load the mod_cband module:LoadModule cband_module modules/mod_cband.so
Configuration Directives
New commands from 0.9.7.0 version:- CBandDefaultExceededCode - the http code sent to the user when the quota is exceeded
Units accepted in various directives:
- transfer speeds:
- kbps, Mbps, Gbps - multiples of "bits per second", respectively: 1024, 1024*1024 and 1024*1024*1024 bps
- kb/s, Mb/s, Gb/s - multiples of "bytes per second", respectively: 1024, 1024*1024 and 1024*1024*1024 b/s
- defaults to kbps
- transfer quotas:
- K, M, G - multiples of bytes, respectively: 1000, 1000*1000 and 1000*1000*1000 bytes
- Ki, Mi, Gi - multiples of bytes, respectively: 1024, 1024*1024 and 1024*1024*1024 bytes
- defaults to K
- time periods:
- S, M, H, D, W - multiples of seconds: Seconds, Minutes, Hours, Days, Weeks; respectively: 1, 60, 3600, 86400, 604800 seconds
- defaults to S
| Name | CBandDefaultExceededURL |
| Description | Default URL where mod_cband should redirect all requests to the virtualhost or user when the configured transfer limit is exceeded NOTE: If you don't specify the exceeded URL location then standard 503 Service Unavailable will be sent |
| Context | Server config |
| Syntax | CBandDefaultExceededURL URL |
| Name | CBandDefaultExceededCode NEW |
| Description | The http code sent to the user when the configured transfer is exceeded |
| Context | Server config |
| Syntax | CBandDefaultExceededCode HTTP_CODE |
| Example | CBandDefaultExceededCode 509 |
| Name | CBandScoreFlushPeriod |
| Description | Specifies a period after which the score for the virtualhost or user is written to the scoreboard file. Use this to improve mod_cband's performance |
| Default | 1 |
| Context | Server config |
| Syntax | CBandScoreFlushPeriod number_of_requests |
| Example | CBandScoreFlushPeriod 100 Any virtualhost's or user's scoreboard will be saved after 100 requests |
| Name | CBandSpeed |
| Description | Specifies a maximal speed for a virtualhost |
| Context | |
| Syntax | CBandSpeed kbps rps max_conn kbps - maximal transfer speed in [kMG]bps or [kMG]B/s rps - maximal requests per second max_conn - maximal number of simultaneous connections |
| Example | CBandSpeed 1024 10 30 Specifies maximal speed 1024kbps (1024 * 1024 bits per second), maximal 10 requests per second and with a maximum of 30 open connections NOTE:This feature is available from version 0.9.6.0 |
| Name | CBandRemoteSpeed |
| Description | Specifies maximal speed for any remote client |
| Context | |
| Syntax | CBandRemoteSpeed kbps rps max_conn kbps - maximal transfer speed in [kMG]bps or [kMG]B/s rps - maximal requests per second max_conn - maximal number of simultaneous connections |
| Example | CBandRemoteSpeed 20kb/s 3 3 Specifies maximal speed 20kB/s (20 * 1024 bytes per second), maximal 3 requests per second and 3 open connections for any remote client NOTE:This feature is available from version 0.9.6.1-rc2 |
| Name | CBandClassRemoteSpeed |
| Description | Specifies maximal speed for any remote client from some destination class |
| Context | |
| Syntax | CBandClassRemoteSpeed class_name kbps rps class_name - name of defined destination class kbps - maximal transfer speed in kbps or kB/s rps - maximal requests per second max_conn - maximal number of simultaneous connections |
| Example | CBandClassDst 66.249.64/24 CBandClassDst 66.249.65/24 CBandClassDst 66.249.79/24 CBandClassRemoteSpeed googlebot_class 20kb/s 2 3 -Specifies maximal speed 20kB/s (20 * 1024 bytes per second), maximal 2 requests per second and 3 open connections for any remote client from class googlebot_class NOTE:This feature is available from version 0.9.6.1-rc2 |
| Name | CBandRandomPulse |
| Description | Turns On or Off the random pulse generator for data sending Random pulse generator is a part of the speed-limiting implementation of mod_cband. This directive changes the way a connection's speed is determined and enforced. The connections' speeds are measured within some time period and then provided for in that period. When r.p.g. is enabled this period is chosen randomly, providing for a statisticaly saner load distribution. Disabling this causes spikes both in bandwidth and cpu usages |
| Context | Global |
| Syntax | CBandRandomPulse On/Off |
| Name | CBandLimit |
| Description | Specifies bandwidth limit for virtualhost |
| Context | |
| Syntax | CBandLimit limit limit - bandwidth quota size, available units: K (kilo), M (mega), G (giga), Ki (kibi), Mi (mebi), Gi (gibi) |
| Example | CBandLimit 10M Specifies 10 * 1000 * 1000 bytes bandwidth quota CBandLimit 10Mi Specifies 10 * 1024 * 1024 bytes bandwidth quota IMPORTANT NOTE: the meaning of K, M and G changed with version 0.9.6.0. Check your config |
| Name | CBandClassLimit |
| Description | Specifies bandwidth limit for virtualhost's destination class |
| Context | |
| Syntax | CBandClassLimit class_name limit class_name - the name of defined class limit - bandwidth quota size, available units: K (kilo), M (mega), G (giga), Ki (kibi), Mi (mebi), Gi (gibi) IMPORTANT NOTE: the meaning of K, M and G changed with version 0.9.6.0. Check your config |
| Name | CBandExceededURL |
| Description | Specifies a URL where mod_cband should redirect all requests to a virtualhost when the configured transfer limit is exceeded NOTE: If you don't specify the exceeded URL location then standard 503 Service Unavailable will be sent |
| Context | |
| Syntax | CBandExceededURL URL |
| Name | CBandExceededSpeed |
| Description | Specifies maximal speed to which mod_cband slows down a virtualhost when the configured transfer limit is exceeded |
| Context | |
| Syntax | CBandExceededSpeed kbps rps max_conn kbps - maximal transfer speed in kbps or kB/s rps - maximal requests per second max_conn - maximal number of simultaneous connections NOTE:This feature is available from version 0.9.6.0 |
| Name | CBandScoreboard |
| Description | Specifies virtualhost's scoreboard file |
| Context | |
| Syntax | CBandScoreboard path NOTE: The path must be writeable for the apache-user |
| Name | CBandPeriod |
| Description | Specifies a period after which a virtualhost's usages are cleared |
| Context | |
| Syntax | CBandPeriod period period - available units: S (seconds), M (minutes), H (hours), D (days), W (weeks) |
| Example | CBandPeriod 1W CBandPeriod 14D CBandPeriod 60M |
| Name | CBandPeriodSlice |
| Description | Specifies the period slice length |
| Default | slice_len = limit |
| Context | |
| Syntax | CBandPeriodSlice slice_length |
| Example | CBandLimit 100G CBandPeriod 4W CBandPeriodSlice 1W A period will be divided into 4 small slices (4W/1W = 4). Each slice has 100G/4=25G bandwidth limit. After 1W slice limit will be 50G, after 2W will be 75G ... |
| Name | |
| Description | Define a new cband user |
| Context | Server config |
| Syntax |
| Name | CBandUserSpeed |
| Description | Specifies maximal speed for a cband user |
| Context | |
| Syntax | CBandUserSpeed kbps rps max_conn kbps - maximal transfer speed in kbps or kB/s rps - maximal requests per second max_conn - maximal number of simultaneous connections |
| Example | CBandUserSpeed 100kb/s 10 5 Specifies maximal speed 100 kB/s (100 * 1024 bytes per second), maximal 10 requests per second and 5 open connections NOTE:This feature is available from version 0.9.6.0 |
| Name | CBandUserLimit |
| Description | Specifies bandwidth limit for a cband user |
| Context | |
| Syntax | CBandUserLimit limit limit - bandwidth quota size, available units: K (kilo), M (mega), G (giga), Ki (kibi), Mi (mebi), Gi (gibi) |
| Example | CBandUserLimit 10M Specifies 10 * 1000 * 1000 bytes bandwidth quota CBandUserLimit 10Mi Specifies 10 * 1024 * 1024 bytes bandwidth quota IMPORTANT NOTE: the meaning of K, M and G changed with version 0.9.6.0. Check your config |
| Name | CBandUserClassLimit |
| Description | Specifies bandwidth limit for a cband user's destination class |
| Context | |
| Syntax | CBandUserClassLimit class_name limit class_name - the name of defined class limit - bandwidth quota size, available units: K (kilo), M (mega), G (giga), Ki (kibi), Mi (mebi), Gi (gibi) IMPORTANT NOTE: the meaning of K, M and G changed with version 0.9.6.0. Check your config |
| Name | CBandUserExceededURL |
| Description | Specifies a URL where mod_cband should redirect all requests to user's virtualhost when the configured transfer limit is exceeded NOTE: If you don't specify the exceeded URL location then standard 503 Service Unavailable will be sent |
| Context | |
| Syntax | CBandUserExceededURL URL |
| Name | CBandUserExceededSpeed |
| Description | Specifies maximal speed to which mod_cband slows down user when the configured transfer limit is exceeded NOTE: CBandUserExceededURL must not be used if you want to only slow down user's pages with CBandUserExceededSpeed directive |
| Context | |
| Syntax | CBandUserExceededSpeed kbps rps max_conn kbps - maximal transfer speed in kbps or kB/s rps - maximal requests per second max_conn - maximal number of simultaneous connections NOTE:This feature is available from version 0.9.6.0 |
| Name | CBandUserScoreboard |
| Description | Specifies a user's scoreboard file |
| Context | |
| Syntax | CBandUserScoreboard path NOTE: The path must be writeable for the apache-user |
| Name | CBandUserPeriod |
| Description | Specifies a period after which a user's usages are cleared |
| Context | |
| Syntax | CBandUserPeriod period period - available units: S (seconds), M (minutes), H (hours), D (days), W (weeks) |
| Example | CBandUserPeriod 1W CBandUserPeriod 14D CBandUserPeriod 60M |
| Name | CBandUserPeriodSlice |
| Description | Specifies a period slice length |
| Default | slice_len = limit |
| Context | |
| Syntax | CBandUserPeriodSlice slice_length |
| Example | CBandUserLimit 100G CBandUserPeriod 4W CBandUserPeriodSlice 1W A period will be divided into 4 small slices (4W/1W = 4). Each slice has 100G/4=25G bandwidth limit. After 1W slice limit will be 50G, after 2W will be 75G ... |
Status Handler Configuration Example
To view actual bandwidth limits, usages, users, scoreboards, add the following lines into the config file:Then you can access the status page with a URL like:SetHandler cband-status SetHandler cband-status-me
http://server_name/cband-status
http://server_name/cband-status-me
An example of the cband-status is available here
An example of the cband-status-me is available here
In versions >=0.9.5-rc1 you can also view /cband-status handler in the XML format:
http://server_name/cband-status?xml
http://server_name/cband-status-me?xml
An example of the cband-status in the XML format is available here
An example of the cband-status-me in the XML format is available here
Bandwidth Speed Configuration Example
DocumentRoot /var/www/xyz.org/ ServerName xyz.org CustomLog /var/log/apache2/xyz.org.access combined ErrorLog /var/log/apache2/xyz.org.access.error RewriteEngine On RewriteOptions inherit # Maximal 1024kbps speed for this virtualhost # Maximal 10 requests per second for this virtualhost # Maximal 30 open connections for this virtualhost CBandSpeed 1024 10 30 # Maximal 10kB/s speed, 3 requests/s and 2 open connections for any remote client CBandRemoteSpeed 10kb/s 3 2 # Maximal 20kB/s speed, 2 requests/s and 3 open connections for remote # clients from class googlebot_class :P CBandClassRemoteSpeed googlebot_class 20kb/s 2 3
Bandwidth Quota Configuration Example
per-virtualhost bandwidth limiting configuration
Next, you may define virtualhost's bandwidth limits, URL location and the path to scoreboard files for individual virtualhosts:# specify default 'bandwidth exceeded' locationCBandDefaultExceededURL http://haha.org/bandwidth_exceeded.htmlDocumentRoot /var/www/xyz.org/ ServerName xyz.org CustomLog /var/log/apache2/xyz.org.access combined ErrorLog /var/log/apache2/xyz.org.access.error RewriteEngine On RewriteOptions inherit # 100MB virtualhost bandwidth limit CBandLimit 100000 # redirect to http://abc.org/bandwidth_exceeded.html # when the limit has been reached CBandExceededURL http://abc.org/bandwidth_exceeded.html # virtualhost's scoreboard file CBandScoreboard /var/run/apache2/xyz.org.scoreboard # a period of time after which the scoreboard will be cleared (30 minutes) # (only in >=0.9.5-rc2) CBandPeriod 30M
per-user bandwidth limiting configuration (only in versions >=0.9.1)
In versions >=0.9.1 you can define limits for users and assign virtualhosts to them# define user 'dembol'# 200MB bandwidth limit for user 'dembol' CBandUserLimit 200000 # redirect to http://abc.org/bandwidth_exceeded.html # when the limit has been reached CBandUserExceededURL http://abc.org/bandwidth_exceeded.html # user's scoreboard file CBandUserScoreboard /var/run/apache2/dembol.scoreboard # a period of time after which the scoreboard will be cleared (5 weeks) # (only in >=0.9.5-rc2) CBandUserPeriod 5W
# assign virtualhost 'xyz.org' to user 'dembol'ServerName xyz.org # Specify virtualhost's owner CBandUser dembol # assign virtualhost 'aga.org' to user 'dembol'ServerName aga.org # Specify virtualhost's owner CBandUser dembol
per-user and per-virtualhost bandwidth limiting configuration (only in versions >=0.9.1)
In versions >=0.9.1 you can also mix per-user and per-virtualhost bandwidth limiting techniques# define user 'dembol'# 200MB bandwidth limit for user 'dembol' CBandUserLimit 200000 # redirect to http://abc.org/bandwidth_exceeded.html # when the limit has been reached CBandUserExceededURL http://abc.org/bandwidth_exceeded.html # user's scoreboard file CBandUserScoreboard /var/run/apache2/dembol.scoreboard # a period of time after which the scoreboard will be cleared (4 days) # (only in >=0.9.5-rc2) CBandUserPeriod 4D
# assign virtualhost 'xyz.org' to user 'dembol'ServerName xyz.org # Specify virtualhost's owner CBandUser dembol # 100MB virtualhost bandwidth limit CBandLimit 100000 # redirect to http://abc.org/bandwidth_exceeded.html # when the limit has been reached CBandExceededURL http://abc.org/bandwidth_exceeded.html # virtualhost's scoreboard file CBandScoreboard /var/run/apache2/xyz.org.scoreboard # a period of time after which the scoreboard will be cleared (50 minutes) # (only in >=0.9.5-rc2) CBandPeriod 50M # assign virtualhost 'aga.org' to user 'dembol'ServerName aga.org # Specify virtualhost's owner CBandUser dembol
per-destination bandwidth limiting configuration (only in >=0.9.5-rc1 versions)
In >= 0.9.5-rc1 you can limit traffic to some destination classes. The destination classes are defined by# define 'class_1'CBandClassDst 217.172.231.67 CBandClassDst 127/8 CBandClassDst 192.168.0.0/24 CBandClassDst 10.0.0.20 # define 'class_2'CBandClassDst 192.168.100.100 CBandClassDst 153.19/16 CBandUserLimit 1000000 CBandUserExceededURL http://edns.pl/bandwidth_exceeded.html CBandUserScoreboard /home/dembol/write/user.dembol.scoreboard # 500MB limit for 'class_2' CBandUserClassLimit class_2 500000 ... CBandUser dembol # 1GB limit for 'class_1' CBandClassLimit class_1 1000000 # a period of time after which the scoreboard will be cleared (120 seconds) # (only in >=0.9.5-rc2) CBandPeriod 120S
Configuration file example
An example of the Apache 2 vhosts.conf file for the mod_cband is available herePerformance Tests
mod_cband without CBandScoreFlushPeriod directive| MPM prefork | MPM worker | MPM perchild | MPM event | MPM leader | |
| with mod_cband | 316.63 rps | 346.89 rps | ~ | 297.36 rps | ~ |
| without mod_cband | 447.76 rps | 406.91 rps | ~ | 425.13 rps | ~ |
| MPM prefork | MPM worker | MPM perchild | MPM event | MPM leader | |
| with mod_cband | 405.17 rps | 365.22 rps | ~ | 414.60 rps | ~ |
| without mod_cband | 447.76 rps | 406.91 rps | ~ | 425.13 rps | ~ |
| ./configure --with-mpm=$1 \ --enable-layout=Slackware \ --enable-v4-mapped \ --enable-cache \ --enable-disk-cache --enable-mem-cache \ --enable-deflate \ --enable-ssl \ --enable-mods-shared=all \ --with-uid=apache --with-gid=apache \ --with-gdbm --with-berkeley-db |
Machine: 2xPentium II 333MHz, 320MB RAM (full specification)
Network: 100Mbps ethernet
Test command:
| httperf --server 192.168.0.25 --port 8 --num-conns 1000 --uri http://www.traktor.pl --hog |