imip-agent

Annotated docs/wiki/SystemUsers

1024:48b37822d2a0
1004:4bc73eb1e076
2016-01-29 Paul Boddie file changeset files shortlog Moved common test initialisation into a separate script.
paul@955 1 
= System Users and Filesystem Access =
paul@955 2 
 
 paul@955      3 
The data handled by imip-agent needs to be accessible to other software,
 
 paul@955      4 
notably mail handling software and Web server software. Two approaches to
 
 paul@955      5 
[[../MailIntegration|e-mail integration]] affect the choice of system users
 
 paul@955      6 
and groups:
 
 paul@955      7 
 
 paul@955      8 
{{{#!table
 
 paul@1004      9 
'''Integration Method''' || '''System Users and Groups''' || '''Suitable for...'''
 
 paul@955     10 
==
 
 paul@1004     11 
Using a dedicated `lmtp` group
 
 paul@955     12 
|| `imip-agent` belongs to `lmtp` and `www-data` groups<<BR>>
 
 paul@955     13 
.. `www-data` also belongs to the `lmtp` group
 
 paul@1004     14 
|| [[../MailIntegration/LMTP|LMTP delivery]] and
 
 paul@1004     15 
.. [[../MailIntegration/LocalSMTP|Local SMTP delivery]]
 
 paul@955     16 
==
 
 paul@1004     17 
Using an existing group
 
 paul@955     18 
|| `imip-agent` belongs to the `www-data` group
 
 paul@1004     19 
|| [[../MailIntegration/LocalSMTP|Local SMTP delivery]]
 
 paul@955     20 
}}}
 
 paul@955     21 
 
 paul@955     22 
The corresponding strategies are described in more detail below.
 
 paul@955     23 
 
 paul@1004     24 
== Using a Dedicated LMTP-Related Group ==
 
 paul@955     25 
 
 paul@1004     26 
Here, imip-agent's programs can run in a way that permits them to initiate
 
 paul@1004     27 
[[../MailIntegration/LMTP|LMTP delivery]] (requiring suitable local privileges
 
 paul@1004     28 
to communicate with the mail storage solution) whilst allowing the Web server
 
 paul@1004     29 
to read data written by the [[../AgentPrograms|agent programs]].
 
 paul@955     30 
 
 paul@955     31 
A system group needs to be created for LMTP delivery and for certain users to
 
 paul@955     32 
share resources:
 
 paul@955     33 
 
 paul@955     34 
{{{
 
 paul@955     35 
addgroup lmtp
 
 paul@955     36 
}}}
 
 paul@955     37 
 
 paul@955     38 
This group should be employed for LMTP delivery by systems like Cyrus and
 
 paul@984     39 
Dovecot. See the [[../MailboxIntegration|mail storage guide]] for more
 
 paul@955     40 
information.
 
 paul@955     41 
 
 paul@955     42 
A system user needs to be created and to belong to certain groups in order to
 
 paul@955     43 
deliver messages to mail stores and to publish resources on the Web:
 
 paul@955     44 
 
 paul@955     45 
{{{
 
 paul@955     46 
useradd -d /var/lib/imip-agent -m -U -G lmtp,www-data -r imip-agent
 
 paul@955     47 
}}}
 
 paul@955     48 
 
 paul@955     49 
Store details and published resources need to be accessible by the `imip-agent`
 
 paul@955     50 
and `www-data` users. Thus, `www-data` also needs to belong to the `lmtp` group:
 
 paul@955     51 
 
 paul@955     52 
{{{
 
 paul@955     53 
adduser www-data lmtp
 
 paul@955     54 
}}}
 
 paul@955     55 
 
 paul@1004     56 
{{{#!wiki tip
 
 paul@1004     57 
This configuration should also work with the
 
 paul@1004     58 
[[../MailIntegration/LocalSMTP|local SMTP delivery]] method, because the `lmtp`
 
 paul@1004     59 
group membership will be superfluous for the `imip-agent` user. So, if the use
 
 paul@1004     60 
of such a group is not problematic, this approach is a reasonable default choice.
 
 paul@1004     61 
Moreover, there may be a need to create the `lmtp` group, anyway, so that MTAs
 
 paul@1004     62 
can deliver to [[../MailboxIntegration|mail storage solutions]].
 
 paul@1004     63 
}}}
 
 paul@1004     64 
 
 paul@1004     65 
== Using an Existing Group ==
 
 paul@955     66 
 
 paul@955     67 
Here, imip-agent's programs run in a way that permits local SMTP delivery
 
 paul@955     68 
(which merely needs the ability to connect to a local network service) whilst
 
 paul@1004     69 
allowing the Web server to read data written by the
 
 paul@1004     70 
[[../AgentPrograms|agent programs]]. This approach provides a means of keeping
 
 paul@1004     71 
imip-agent separate from mail-related users and groups.
 
 paul@984     72 
 
 paul@955     73 
A system user needs to be created and to belong to certain groups in order to
 
 paul@955     74 
deliver messages to mail stores and to publish resources on the Web:
 
 paul@955     75 
 
 paul@955     76 
{{{
 
 paul@955     77 
useradd -d /var/lib/imip-agent -m -U -G www-data -r imip-agent
 
 paul@955     78 
}}}
 
 paul@955     79 
 
 paul@955     80 
Again, the `tools/init.sh` script will initialise directories for stored and
 
 paul@955     81 
published data. The `tools/config.sh` script should be edited and the group
 
 paul@955     82 
redefined as follows:
 
 paul@955     83 
 
 paul@955     84 
{{{
 
 paul@955     85 
IMIP_AGENT_GROUP=www-data
 
 paul@955     86 
}}}
 
 paul@955     87 
 
 paul@955     88 
If already installed, the `/etc/imip-agent/config.sh` script should be edited
 
 paul@955     89 
instead. See the [[../Configuration|configuration guide]] for more information.
 
 paul@955     90 
 
 paul@955     91 
With local SMTP delivery, the mail system will need to be configured to route
 
 paul@955     92 
messages for local recipients. See the [[../MailIntegration/LocalSMTP|local SMTP]]
 
 paul@955     93 
description of mail configuration for more information.
 
 paul@955     94 
 
 paul@955     95 
== Updating the Configuration ==
 
 paul@955     96 
 
 paul@955     97 
Once the necessary decisions have been taken here, the system's
 
 paul@955     98 
[[../Configuration|configuration]] will need updating so that the software and
 
 paul@955     99 
tools will work correctly.