An Ansible role to set a host's hostname and manage /etc/hosts entries.
| Variable Name | Description | Required | Default Value | Type |
|---|---|---|---|---|
| hosts_hostname | Defines the system's hostname, and manages its /etc/hosts entries. | no | {} | dictionary |
| hosts_add_hosts | Defines additional /etc/hosts entries. | no | [{}] | list of dictionaries |
| hosts_backup | Backup /etc/hosts when changing the file. | no | True | boolean |
| hosts_set_hostname | Set hostname on system. Set False to only manage /etc/hosts | no | True | boolean |
if you do not set hosts_hostname (not required) a default ipv4 loopback line will be created in /etc/hosts if hosts_add_hosts is defined, but ipv6 loopback will not get created
| Field Name | Description | Required | Default Value | Type |
|---|---|---|---|---|
| hostname | Short (non-fqdn) hostname of the server | yes | n/a | string |
| domain | Domain name of the server | yes | n/a | string |
| alias | Additional aliases the server is known by (cnames) | no | n/a | list |
| alias_loopback | Whether or not to add the hostname and aliases to the /etc/hosts loopback line(s). | yes | n/a | boolean |
| add_ips | Additional IP addresses for the server in /etc/hosts. | no | n/a | list |
| ipv6 | Whether IPv6 is used on the system (sets IPv6 loopback line) | yes | n/a | boolean |
Here is an example of using the hosts_hostname dictionary in a variable file:
---
hosts_hostname:
hostname: "foo"
domain: "bar.com"
alias:
- "web1"
- "intranet"
alias_loopback: False # Don't modify localhost loopback in /etc/hosts
add_ips:
- "192.168.122.100" # main NIC
- "10.10.10.100" # another NIC
# you could add ipv6 addresses to this list as well
ipv6: False # Don't create ipv6 loopback entries This will produce lines in /etc/hosts as such:
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
192.168.122.100 foo.bar.com foo web1 intranet
10.10.10.100 foo.bar.com foo web1 intranet
| Field Name | Description | Required | Default Value | Type |
|---|---|---|---|---|
| hostname | Short (non-fqdn) hostname of the server | yes | n/a | string |
| domain | Domain name of the server | yes | n/a | string |
| ip_addr | IP address of the server | yes | n/a | string |
| comment | Comment line to put above entry in /etc/hosts | no | n/a | string |
| alias | Additional aliases the server is known by (cnames) | no | n/a | list |
Here is an example of using the hosts_hostname dictionary in a variable file:
hosts_add_hosts:
- hostname: "otherserver1"
domain: "bar.net"
ip_addr: "10.100.5.66"
comment: "External database server"
alias:
- "db1"
- "database"
- "db"
- hostname: "anotherserver"
domain: "coolsite.com"
ip_addr: "1.2.3.4"
comment: "A cool website"This will produce lines in /etc/hosts as such:
# External database server
10.100.5.66 otherserver1.bar.net otherserver1 db1 database db
# A cool website
1.2.3.4 anotherserver.coolsite.com anotherserver
host_vars/myserver1.yml contents:
---
# Set host specific hostname and /etc/hosts entries
hosts_hostname:
hostname: "myserver1"
domain: "foo.bar.com"
alias:
- "webserver1.someotherdomain.com"
- "www"
- "db1"
- "dubdubdub.dubs.com"
alias_loopback: False
add_ips:
- "192.168.122.50"
- "192.168.122.51"
- "192.168.122.52"
ipv6: True---
- name: "Set hostname and /etc/hosts entries"
hosts: "all"
tasks:
- name: "Ensure hostname and /etc/hosts are in desired state"
include_role:
name: "ahuffman.hosts"
vars:
hosts_backup: False
hosts_set_hostname: True
hosts_add_hosts:
- hostname: "myserver2"
domain: "foo.bar.com"
ip_addr: "192.168.122.60"
comment: 'The other webserver that does stuff'
alias:
- "intranet.externaldomain.com"
- "intranet"
- "helpdesk.helpme.com"
- "helpdesk"
- name: "Another App server"
hostname: "appserver2"
domain: "bar.com"
ip_addr: "192.168.122.70"
comment: "App server 1"The /etc/hosts file produced by the above example would look like:
# Ansible managed
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.122.50 myserver1.foo.bar.com myserver1 webserver1.someotherdomain.com www db1 dubdubdub.dubs.com
192.168.122.51 myserver1.foo.bar.com myserver1 webserver1.someotherdomain.com www db1 dubdubdub.dubs.com
192.168.122.52 myserver1.foo.bar.com myserver1 webserver1.someotherdomain.com www db1 dubdubdub.dubs.com
# The other webserver that does stuff
192.168.122.60 myserver2.foo.bar.com myserver2 intranet.externaldomain.com intranet helpdesk.helpme.com helpdesk
# App server 1
192.168.122.70 appserver2.bar.com appserver2