I’m in the process of setting up a server at home to replace an old one. I’m maintaining the new one via Ansible to try and get keep as tidy as possible. Part of the setup involves setting up a bridge interface so that I can run kvm virtual machines on the box.
In order to make the box a little more stable I decided to make the ethernet settings static rather than via DHCP. Unfortunately ansible doesn’t really have a nice standard way of setting up network ports (there are a few modules around but none in the main distribution). After looking around I decided just to make a simple ansible role to handle the files.
The machine is running centos7. The networking initially looked like:
/etc/sysconfig/network-scripts/ifcfg-enp2s0 :::::::::::::: HWADDR=9C:B6:54:07:E8:49 TYPE=Ethernet BOOTPROTO=dhcp NAME=enp2s0 ONBOOT=yes #
I decided the easiest way was to just manually create and copy the files. So I created a static_networking role.
roles/static_networking/handlers/main.yml roles/static_networking/files/grey/ifcfg-enp2s0 roles/static_networking/files/grey/ifcfg-bridge0 roles/static_networking/tasks/main.yml roles/static_networking/tasks/setup-redhat.yml
Inside the tasks the main.yml just loads up the setup-redhat.yml which is:
---
- name: copy files if they are listed in var
copy: src={{ ansible_hostname }}/ifcfg-{{ item }} dest=/etc/sysconfig/network-scripts/ owner=root mode=0644
with_items: static_interfaces
notify:
- restart network
Which is fairly simple. It just goes though a list of “static_interfaces” for a host and copies these files from the local machine to the machine I am setting up. If the copy makes any changes it sends a notify.
For the machine “grey” I just create some entries in hosts_vars/grey.yml
static_interfaces: - enp2s0 - bridge0
and then the files themselves:
roles/static_networking/files/grey/ifcfg-bridge0 :::::::::::::: DEVICE="bridge0" ONBOOT="yes" TYPE=Bridge BOOTPROTO=static IPADDR=10.1.1.28 NETMASK=255.255.255.0 GATEWAY=10.1.1.1 :::::::::::::: roles/static_networking/files/grey/ifcfg-enp2s0 :::::::::::::: DEVICE="enp2s0" ONBOOT="yes" NM_CONTROLLED="no" BOOTPROTO="none" BRIDGE=bridge0 HWADDR="9c:b6:54:07:e8:49"
which are the actual files to be copied. If any files are actually updated the handler will be triggered
roles/static_networking/handlers/main.yml --- # Called by "name" when network config files are changed - name: restart network service: name=network state=restarted
Overall it seems to work and I only broke networking once (the ip on enp2s0 keep getting re-added until I forced network manager to forget about it). I wouldn’t really recommend this sort of thing for non-trivial sites though. Keeping per-site configs in roles isn’t really the best way to do things.
