mirmon - monitor the state of mirrors

- NAME
- SYNOPSIS
- OPTIONS
- USAGE
- CONFIG FILE

- location
- syntax

- CONFIG FILE : required entries

- project_name name
- project_url url
- mirror_list file-name
- web_page file-name
- icons directory-name
- probe program + arguments
- state file-name
- countries file-name

- CONFIG FILE : optional entries

- max_probes number
- timeout seconds
- project_logo logo
- htm_head html
- htm_top html
- htm_foot html
- put_histo top|bottom|nowhere
- min_poll time-spec
- max_poll time-spec
- min_sync time-spec
- max_sync time-spec
- no_randomize
- no_add_slash
- list_style plain|apache
- site_url site url
- env key value
- include file-name
- show
- exit

- STATE FILE FORMAT
- INSTALLATION

- general
- installation suggestions

- SEE ALSO
- AUTHOR

# NAME

mirmon - monitor the state of mirrors

# SYNOPSIS

      mirmon [ -v ] [ -q ] [ -t timeout ] [ -get opt ] [ -c conf ]

# OPTIONS

      option v   : be verbose
      option q   : be quiet
      option t   : set timeout [ default 300 ] ;
      option get : 'all'    : probe all sites
                 : 'update' : probe a selection of the sites (see doc)
      option c   : configuration file ; default list :
                   ./mirmon.conf $HOME/.mirmon.conf /usr/local/etc/mirmon.conf
      -------------------------------------------------------------------
      Mirmon normally only reports errors and changes in the mirror list.
      -------------------------------------------------------------------

# USAGE

The program is intended to be run by cron every hour.

      42 * * * * perl /path/to/mirmon -get update

It quietly probes a subset of the sites in a given list, writes the results in the 'state' file and generates a web page with the results. The subset contains the sites that are new, bad and/or not probed for a specified time.

When no 'get' option is specified, the program just generates a new web page from the last known state.

The program checks the mirrors by running a (user specified) program on a pipe. A (user specified) number of probes is run in parallel using nonblocking IO. When something can be read from the pipe, it switches the pipe to blocking IO and reads one line from the pipe. Then it flushes and closes the pipe. No attempt is made to kill the probe.

The probe should return something that looks like

      1043625600 ...

that is, a line of text starting with a timestamp. The exit status of the probe is ignored.

# CONFIG FILE

## location

A config file can be specified with the -c option. If -c is not used, the program looks for a config file in

- ./mirmon.conf
- $HOME/.mirmon.conf
- /usr/local/etc/mirmon.conf

## syntax

A config file looks like this :

      +--------------------------------------------------
      |# lines that start with '#' are comment
      |# blank lines are ignored too
      |# tabs are replaced by a space
      |
      |# the config entries are 'key' and 'value' pairs
      |# a 'key' begins in column 1
      |# the 'value' is the rest of the line
      |somekey  A_val B_val ...
      |otherkey X_val Y_val ...
      |
      |# indented lines are glued
      |# the next three lines mean 'somekey part1 part2 part3'
      |somekey part1
      |  part2
      |  part3
      |
      |# lines starting with a '+' are concatenated
      |# the next three lines mean 'somekey part1part2part3'
      |somekey part1
      |+ part2
      |+ part3
      |
      |# lines starting with a '.' are glued too
      |# don't use a '.' on a line by itself
      |# 'somekey' gets the value "part1\n part2\n part3"
      |somekey part1
      |. part2
      |. part3
      +--------------------------------------------------

# CONFIG FILE : required entries

## project_name name

Specify a short plaintext name for the project.

      project_name Apache
      project_name CTAN

## project_url url

Specify an url pointing to the 'home' of the project.

      project_url http://www.apache.org/

## mirror_list file-name

Specify the file containing the mirrors to probe.

      mirror_list /path/to/mirror-list

If your mirror list is generated by a program, use

      mirror_list /path/to/program arg1 ... |

Two formats are supported :

- plain : lines like

      us http://www.tux.org/ [email] ...
      nl http://apache.cs.uu.nl/dist/ [email] ...
      nl rsync://archive.cs.uu.nl/apache-dist/ [email] ...

- apache : lines like those in the apache mirrors.list

      ftp  us ftp://ftp.tux.org/pub/net/apache/dist/ user@tux.org ...
      http nl http://apache.cs.uu.nl/dist/ user@cs.uu.nl ...

Note that in style 'plain' the third item is reserved for an optional email address : the site's contact address.

Specify the required format with 'list_style' (see below). The default style is 'plain'.

## web_page file-name

Specify where the html report page is written.

## icons directory-name

Specify the directory where the icons can be found, relative to the web_page, or relative to the DOCUMENTROOT of the web server.

If/when the web_page lives in directory `.../mirmon/` and the icons live in directory `.../mirmon/icons/`, specify

      icons icons

If/when the icons live in `/path/to/DOCUMENTROOT/icons/mirmon/`, specify

      icons /icons/mirmon

## probe program + arguments

Specify the program+args to probe the mirrors. Example:

      probe /usr/bin/wget -q -O - -T %TIMEOUT% -t 1 %URL%TIME

Before the program is started, %TIMEOUT% and %URL% are substituted with the proper timeout and url values.

Here it is assumed that each hour the root server writes a timestamp in /path/to/archive/TIME, for instance with a crontab entry like

      42 * * * * perl -e 'printf "%s\n", time' > /path/to/archive/TIME

Mirmon reads one line of output from the probe and interprets the first word on that line as a timestamp ; for example :

      1043625600
      1043625600 Mon Jan 27 00:00:00 2003
      1043625600 www.apache.org Mon Jan 27 00:00:00 2003

Mirmon is distributed with a program `probe` that handles ftp, http and rsync urls.

## state file-name

Specify where the file containing the state is written.

The program reads this file on startup and writes the file when mirrors are probed (-get is specified).

## countries file-name

Specify the file containing the country codes; The file should contain lines like

      us - United States
      nl - Netherlands

The mirmon package contains a recent ISO list.

Fake domains like Backup, Master are allowed, and are listed first in the report ; lowercase-first fake domains (like backup) are listed last.

# CONFIG FILE : optional entries

## max_probes number

Optionally specify the number of parallel probes (default 25).

## timeout seconds

Optionally specify the timeout for the probes (default 300).

After the last probe is started, the program waits for <timeout> + 10 seconds, cleans up and exits.

## project_logo logo

Optionally specify (the SRC of the IMG of) a logo to be placed top right on the page.

      project_logo /icons/apache.gif
      project_logo http://www.apache.org/icons/...

## htm_head html

Optionally specify some HTML to be placed before </HEAD>.

      htm_head
        <link REL=StyleSheet HREF="/style.css" TYPE="text/css">

## htm_top html

Optionally specify some HTML to be placed near the top of the page.

      htm_top testing 1, 2, 3

## htm_foot html

Optionally specify HTML to be placed near the bottom of the page.

      htm_foot
        <HR>
        <A HREF="..."><IMG SRC="..." BORDER=0></A>
        <HR>

## put_histo top|bottom|nowhere

Optionally specify where the age histogram must be placed. The default is 'top'.

## min_poll time-spec

For 'min_poll' see next item. A time-spec is a number followed by a unit 's' (seconds), or 'm' (minutes), or 'h' (hours), or 'd' (days). For example '3d' (three days) or '36h' (36 hours).

## max_poll time-spec

Optionally specify the maximum probe interval. When the program is called with option '-get update', all sites are probed which are :

- new
the site appears in the list, but there is no known state

- bad
the last probe of the site was unsuccessful

- old
the last probe was more than 'max_poll' ago.

Sites are not probed if the last probe was less than 'min_poll' ago. So, if you specify

      min_poll 4h
      max_poll 12h

the 'reachable' sites are probed twice daily and the 'unreachable' sites are probed at most six times a day.

The default 'min_poll' is '1h' (1 hour). The default 'max_poll' is '4h' (4 hours).

## min_sync time-spec

Optionally specify how often the mirrors are required to make an update.

The default 'min_sync' is '1d' (1 day).

## max_sync time-spec

Optionally specify the maximum allowable sync interval.

Sites exceeding the limit will be considered 'old'. The default 'max_sync' is '2d' (2 days).

## no_randomize

Mirmon tries to balance the probe load over the hourly mirmon runs. If the current run has a below average number of mirrors to probe, mirmon probes a few extra, randomly chosen mirrors, picked from the runs that have the highest load.

If you don't want this behaviour, use no_randomize.

## no_add_slash

If the url part of a line in the mirror_list doesn't end in a slash ('/'), mirmon adds a slash and issues a warning unless it is in quiet mode.

If you don't want this behaviour, use no_add_slash.

## list_style plain|apache

Optionally specify the format ('plain' or 'apache') of the mirror-list.

See the description of 'mirror_list' above. The default list_style is 'plain'.

## site_url site url

Optionally specify a substitute url for a site.

When access to a site is restricted (in Australia, for instance), another (sometimes secret) url can be used to probe the site. The <site> of an url is the part between '://' and the first '/'.

## env key value

Optionally specify an environment variable.

## include file-name

Optionally specify a file to include.

The specified file is processed 'in situ'. After the specified file is read and processed, config processing is resumed in the file where the `include` was encountered. The include depth is unlimited. However, it is a fatal error to include a file twice under the same name.

## show

When the config processor encounters the 'show' command, it dumps the content of the current config to standout, if option `-v` is specified. This is intented for debugging.

## exit

When the config processor encounters the 'exit' command, it terminates the program. This is intented for debugging.

# STATE FILE FORMAT

The state file consists of lines; one line per site. Each line consists of white space separated fields. The seven fields are :

- field 1 : url
The url as given in the mirror list.

- field 2 : age
The mirror's timestamp found by the last succesful probe, or 'undef' if no probe was ever successful.

- field 3 : status last probe
The status of the last probe, or 'undef' if the mirror was never probed.

- field 4 : time last succesful probe
The timestamp of the last succesful probe or 'undef' if the mirror was never successfully probed.

- field 5 : probe history
The probe history is a list of 's' (for success) and 'f' (for failure) characters indicating the result of the probe. New results are appended whenever the mirror is probed.

- field 6 : state history
The state history consists of a timestamp, a '-' char, and a list of chars indicating a past status: 's' (fresh), 'b' (oldish), 'f' (old), 'z' (bad) or 'x' (skip). The timestamp indicates when the state history was last updated. The current status of the mirror is determined by the mirror's age and a few configuration parameters (min_sync, max_sync, max_poll). The state history is updated when the mirror is probed. If the last update of the history was less than 24 hours ago, the last status is replaced by the current status. If the last update of the history was more than 24 hours ago, the current status is appended to the history. One or more 'skip's is inserted, if the timestamp is two or more days old (when mirmon hasn't run for more than two days).

- field 7 : last probe
The timestamp of the last probe, or 'undef' if the mirror was never probed.

# INSTALLATION

## general

- Note: The (empty) state file must exist before mirmon runs.
- The mirmon repository is here :

      https://subversion.cs.uu.nl/repos/staff.henkp.mirmon/trunk/

- The mirmon tarball is here :

      http://people.cs.uu.nl/henkp/mirmon/mirmon.tar.gz

## installation suggestions

To install and configure mirmon, take the following steps :

- First, make the webdir :

      cd DOCUMENTROOT
      mkdir mirmon

For DOCUMENTROOT, substitute the full pathname of the document root of your webserver.

- Check out the mirmon repository :

      cd /usr/local/src
      svn checkout REPO mirmon

where

      REPO = https://subversion.cs.uu.nl/repos/staff.henkp.mirmon/trunk/

or download the package and unpack it.

- Chdir to directory mirmon :

      cd mirmon

- Create the (empty) state file :

      touch state.txt

- Install the icons in the webdir :

      mkdir DOCUMENTROOT/mirmon/icons
      cp icons/* DOCUMENTROOT/mirmon/icons

- Create a mirror list `mirror_list` ;
Use your favorite editor, or genererate the list from an existing database.

      nl http://archive.cs.uu.nl/your-project/ contact@cs.uu.nl
      uk http://mirrors.this.org/your-project/ mirrors@this.org
      us http://mirrors.that.org/your-project/ mirrors@that.org

The email addresses are optional.

- Create a mirmon config file `mirmon.conf` with your favorite editor.

      # lines must start in the first column ; no leading white space
      project_name ....
      project_url  ....
      mirror_list mirror_list
      state state.txt
      countries countries.list
      web_page DOCUMENTROOT/mirmon/index.html
      icons /mirmon/icons
      probe /usr/bin/wget -q -O - -T %TIMEOUT% -t 1 %URL%TIME

This assumes the project's timestamp is in file `TIME`.

- If you have rsync urls, change the probe line to :

      probe perl /usr/local/src/mirmon/probe -t %TIMEOUT% %URL%TIME

- Run mirmon :

      perl mirmon -v -get all

The mirmon report should now be in 'DOCUMENTROOT/mirmon/index.html'

      http://www.your.project.org/mirmon/

- If/when, at a later date, you want to upgrade mirmon :

      cd /usr/local/src/mirmon
      svn status -u
      svn up

# SEE ALSO

mirmon.pm(3)

# AUTHOR

© 2003-2012 Henk P. Penning, Computer Science Department, Utrecht University
mirmon-2.6 - Fri Mar 30 09:56:03 2012 ; henkp