ext\_unix\_group\_acl(8) System Manager's Manual ext\_unix\_group\_acl(8)

# [NAME](#NAME)

ext\_unix\_group\_acl - Squid UNIX Group ACL helper

# [SYNOPSIS](#SYNOPSIS)

**ext\_unix\_group\_acl \[-d] \[-g** group **] \[-g** group **...] \[-p] \[-s]**

# [DESCRIPTION](#DESCRIPTION)

**ext\_unix\_group\_acl** allows Squid to base access controls on users memberships in UNIX groups.

# [OPTIONS](#OPTIONS)

[**-d**](#d)

Write debug info to stderr. **-g group** Specifies a group name to match.

[**-p**](#p)

Also match the users primary group from **/etc/passwd**

[**-s**](#s)

Strip NT domain name component from user names (/ or \\ separated)

# [CONFIGURATION](#CONFIGURATION)

This **squid.conf** example defines two Squid acls. *usergroup1* matches users in *group1* , and *usergroup2* matches users in *group2* or *group3*

**external\_acl\_type unix\_group %LOGIN /usr/local/squid/libexec/ext\_unix\_group\_acl -p**  
**acl usergroup1 external unix\_group group1**  
**acl usergroup2 external unix\_group group2 group3**

By default up to 11 groups can be matched in one acl (including commandline specified groups). This limit is defined by **MAX\_GROUPS** in the source code.

# [KNOWN ISSUES](#KNOWN_ISSUES)

Does not understand GID aliased groups sometimes used to work around groups size limitations. If you are using GID aliased groups then you must specify each alias by name.

# [AUTHOR](#AUTHOR)

This program was written by *Rodrigo Campos <rodrigo@geekbunker.org>*

This manual was written by *Henrik Nordstrom <hno@squid-cache.org>*

# [COPYRIGHT](#COPYRIGHT)

\* Copyright (C) 1996-2026 The Squid Software Foundation and contributors  
\*  
\* Squid software is distributed under GPLv2+ license and includes  
\* contributions from numerous individuals and organizations.  
\* Please see the COPYING and CONTRIBUTORS files for details.

This program and documentation is copyright to the authors named above.

Distributed under the GNU General Public License (GNU GPL) version 2 or later (GPLv2+).

# [QUESTIONS](#QUESTIONS)

Questions on the usage of this program can be sent to the *Squid Users mailing list* <squid-users@lists.squid-cache.org>

# [REPORTING BUGS](#REPORTING_BUGS)

Bug reports need to be made in English. See https://wiki.squid-cache.org/SquidFaq/BugReporting for details of what you need to include with your bug report.

Report bugs or bug fixes using https://bugs.squid-cache.org/

Report serious security bugs to *Squid Bugs <squid-bugs@lists.squid-cache.org>*

Report ideas for new improvements to the *Squid Developers mailing list* <squid-dev@lists.squid-cache.org>

Additionally bugs or bug-fixes can be reported to *Rodrigo Campos <rodrigo@geekbunker.org>*

# [SEE ALSO](#SEE_ALSO)

[**squid**(8)](/man/enterprise-packages/squid/squid.8), [**group**(5)](/man/enterprise-packages/squid/group.5), [**passwd**(5)](/man/enterprise-packages/squid/passwd.5), [**GPL**(7)](/man/enterprise-packages/squid/GPL.7),  
The Squid FAQ wiki https://wiki.squid-cache.org/SquidFaq  
The Squid Configuration Manual http://www.squid-cache.org/Doc/config/

12 August 2002

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Document: ext_unix_group_acl(8) from squid 7.7-r2 (Chainguard OS)
Source: https://github.com/squid-cache/squid.git