# Best practice for editing /etc/postfix/master.cf **URL:** \ **Category:** Ansible Project\ **Created:** [June 29, 2013, 5:08pm UTC](https://forum.ansible.com/t/best-practice-for-editing-etc-postfix-master-cf/13039 "2013-06-29T17:08:32Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Nolan\_Darilek](https://avatars.discourse-cdn.com/v4/letter/n/919ad9/32.png) [@Nolan\_Darilek](https://forum.ansible.com/u/Nolan_Darilek)\ **Post date:** [June 29, 2013, 5:08pm UTC](https://forum.ansible.com/t/best-practice-for-editing-etc-postfix-master-cf/13039/1 "2013-06-29T17:08:32Z")
I'm trying to add the following to /etc/postfix/master.cf where newlines are significant: sympa unix - n n - - pipe flags=R user=sympa argv=/home/sympa/bin/queue ${recipient} sympabounce unix - n n - - pipe flags=R user=sympa argv=/home/sympa/bin/bouncequeue ${recipient} I'm doing this from different roles. My mail role adds dspam configuration, and the Sympa role I'm writing would add the above. lineinfile isn't easy, because I need to treat each line in the above as a separate play. If I just embed newlines in the play, the first line appears multiple times and the second line only once. I know there's a task that builds a file from snippet templates. Given that this file is appended to by multiple roles, I don't know that this would work. Is it possible to do this kind of edit in a single task, rather than one task per line? To give an example of the ugliness I'm doing now to add dspam: - lineinfile: dest=/etc/postfix/master.cf line="dspam unix - n n - 10 pipe" regexp="dspam\w+unix"    notify:      - restart postfix - lineinfile: dest=/etc/postfix/master.cf line=" flags=Ru user=dspam argv=/usr/bin/dspam --deliver=innocent,spam --user $recipient -i -f $sender -- $recipient" regexp="/usr/bin/dspam"    notify:      - restart postfix Thanks. ---
**Author:** ![Michael\_DeHaan2](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@Michael\_DeHaan2](https://forum.ansible.com/u/Michael_DeHaan2)\ **Post date:** [June 29, 2013, 7:20pm UTC](https://forum.ansible.com/t/best-practice-for-editing-etc-postfix-master-cf/13039/2 "2013-06-29T19:20:25Z")
If you were using the assemble module you would lay down the vairous pieces in something like a /etc/postfix.d/ directory in your various roles and then call your sendmail role _last_ which would merge the fragments into one big list. I’d probably be inclined to just use a template, but I’m not entirely clear on the logic you’d want to put in that template. It might be as simple as {% if ‘xyz’ in group\_names %} {% endif %} But it might be more complicated, I don’t know. I’m not really a fan of using lineinfile unless you have a situation where the end user needs to edit some contents on the box and it’s not truly centrally managed with 100% authority, and in those cases, this can potentially get to be slightly error prone. ---
**Author:** ![Nolan\_Darilek](https://avatars.discourse-cdn.com/v4/letter/n/919ad9/32.png) [@Nolan\_Darilek](https://forum.ansible.com/u/Nolan_Darilek)\ **Post date:** [June 29, 2013, 7:26pm UTC](https://forum.ansible.com/t/best-practice-for-editing-etc-postfix-master-cf/13039/3 "2013-06-29T19:26:15Z")
Ah, hmm, that makes sense. So my mail role would just write out the master.cf template. Is group\_names a list of the roles a host is in, and if so, why the difference in terminology? Is there any way to just append that to the existing /etc/postfix/master.cf rather than build it entirely from scratch? My worry is that I don't want to maintain an entire file whose content may change from Ubuntu release to release. I just want to append my own configuration which will never be present in said file until I put it there. Not sure how that can be possible, but it'd be great if it were. ---
**Author:** ![GW1](https://avatars.discourse-cdn.com/v4/letter/g/c89c15/32.png) [@GW1](https://forum.ansible.com/u/GW1)\ **Post date:** [June 30, 2013, 8:15pm UTC](https://forum.ansible.com/t/best-practice-for-editing-etc-postfix-master-cf/13039/4 "2013-06-30T20:15:42Z")
Hi, “group\_names” is just a list of host groups, has nothing to do with roles. One approach I am using in such cases (and would like a feedback on it) is, eg. for network configuration: - name: create interfaces.d directory file: path=/etc/network/interfaces.d owner=root group=root mode=0700 state=directory - name: create 00\_ansible in interfaces.d template: src=network/interfaces.d/00\_ansible.j2 dest=/etc/network/interfaces.d/00\_ansible.j2 owner=root group=root mode=0644 notify: - assemble interfaces.d - reload networking - name: move 10\_initial to interfaces.d command: /bin/cp -p /etc/network/interfaces /etc/network/interfaces.d/10\_initial creates=/etc/network/interfaces.d/10\_initial notify: - assemble interfaces.d - reload networking So, first create the snippets directory, than put a disclamer (00\_ansible) saying that the file is managed by Ansible with instructions where edits should be made, than copy the original interfaces to 10\_initial in case the later doesn’t exist (in case this is the initial deployment). Then everywhere I add any network configuration I just add it to interfaces.d directory and notify assemble and reload commands. The assemble module concatenates all snippets together alphabetically and the disclamer is on top. Greetings, gw