I am 90% sure this doesn't work because i'm doing it the wrong way, but i can't figure out what is the "right way",I hope you can get my point :
I am trying to access an ipv4 of a certain interface,I have in my hosts file interface_lan = enp4s0 because i need it in a role,so i thought i might just use it to have the IP address of that interface :
"{{hostvars[inventory_hostname]['ansible_{{interface_lan}']['ipv4.address']}}"
with that command,he is looking for "ansible_{{interface_lan}}" but i want him to look for
"ansible_"{{interface_lan}}"" and to consider "{{interface_lan}}" as a variable,not as a string.
I tried my best to explain,sorry if you did not understand you are free to enjoy the rest of your day without helping me, i have been ignoring this line for a few days now.
thank you !
Concatenate the name of the attribute an use it in the index. For example
- hosts: localhost
gather_facts: false
vars:
interface_lan: enp4s0
ansible_enp4s0:
ipv4:
address: 10.1.0.10
tasks:
- set_fact:
ansible_enp4s0: "{{ ansible_enp4s0 }}"
- debug:
msg: "{{ hostvars[inventory_hostname][my_ifc]['ipv4']['address'] }}"
vars:
my_ifc: "{{ 'ansible_' ~ interface_lan }}"
gives (abridged)
msg: 10.1.0.10
Note: set_fact is needed in the example to put the dictionary ansible_enp4s0 into the hostvars.
The indirect addressing of variables without hostvars is possible with the lookup plugin vars. For example
- hosts: localhost
vars:
test_eth0: 10.1.0.10
test_eth1: 10.1.0.11
tasks:
- debug:
msg: "{{ item }}: {{ lookup('vars', 'test_' ~ item ) }}"
loop:
- eth0
- eth1
gives (abridged)
msg: 'eth0: 10.1.0.10'
msg: 'eth1: 10.1.0.11'
Related
I need to get the DNS server(s) from my network, I tried using:
- hosts: localhost
gather_facts: no
tasks:
- name: check resolv.conf exists
stat:
path: /etc/resolv.conf
register: resolv_conf
- name: check nameservers list in resolv.conf
debug:
msg: "{{ contents }}"
vars:
contents: "{{ lookup('file', '/etc/resolv.conf') | regex_findall('\\s*nameserver\\s*(.*)') }}"
when: resolv_conf.stat.exists == True
But this does not quite gives the result I need.
Will it be possible to write a playbook in such a way that the result looks like the below?
hostname;dns1;dns2;dnsN
The declaration below gives the list of nameservers
nameservers: "{{ lookup('file', '/etc/resolv.conf').splitlines()|
select('match', '^nameserver.*$')|
map('split', ' ')|
map('last')|list }}"
You can join the hostname and the items on the list
msg: "{{ inventory_hostname }};{{ nameservers|join(';') }}"
Notes
Example of a complete playbook for testing
- hosts: localhost
vars:
nameservers: "{{ lookup('file', '/etc/resolv.conf').splitlines()|
select('match', '^nameserver.*$')|
map('split', ' ')|
map('last')|list }}"
tasks:
- debug:
var: nameservers
- debug:
msg: |
{{ inventory_hostname }};{{ nameservers|join(';') }}
The simplified declaration below works fine if there is no nameserver.* in the comments
nameservers: "{{ lookup('file', '/etc/resolv.conf')|
regex_findall('\\s*nameserver\\s*(.*)') }}"
Unfortunately, the Linux default file /etc/resolv.conf contains the comment:
| # run "systemd-resolve --status" to see details about the actual nameservers.
This regex will match nameservers.
nameservers:
- s.
You can solve this problem by putting at least one space behind the keyword nameserver.
regex_findall('\\s*nameserver\\s+(.*)') }}"
However, this won't help if there is the keyword nameserver in the comment.
Q: "No filter named 'split'"
A: There is no filter split in Ansible less than 2.11. Use regex_replace instead
nameservers: "{{ lookup('file', '/etc/resolv.conf').splitlines()|
select('match', '^nameserver.*$')|
map('regex_replace', '^(.*) (.*)$', '\\2')|list }}"
Since your regex_findall already creates you a list with all DNS servers, you just need to add the hostname to that list and join the whole list with a semicolon.
- name: check nameservers list in resolv.conf
debug:
msg: >-
{{
(
[ ansible_hostname ] +
lookup('file', '/etc/resolv.conf', errors='ignore')
| regex_findall('\s*nameserver\s*(.*)')
) | join(';')
}}
Which will result in something like (b176263884e6 being the actual hostname of a container):
TASK [check nameservers list in resolv.conf] *****************************
ok: [localhost] =>
msg: b176263884e6;1.1.1.1;4.4.4.4;8.8.8.8
Note that you don't even need the stat task, as you can ignore errors of the lookup with errors='ignore'.
This will, then, give you only the hostname, along with a warning:
TASK [check nameservers list in resolv.conf] *****************************
[WARNING]: Unable to find '/etc/resolv.conf' in expected paths
(use -vvvvv to see paths)
ok: [localhost] =>
msg: b176263884e6
I'm trying to dynamically generate part of an /etc/hosts file with ansible, by gathering facts from all the hosts and looping through the resulting hostvars to grab the IP of the second interface (I need a private IP on this interface, rather than the public IP of the other interface)
I can grab this information from a single host using the following plays:
- name: play 1
hosts: all
- name: play 2
hosts: localhost
connection: local
become: no
tasks:
- debug:
var: hostvars['mysinglehost'].ansible_all_ipv4_addresses[1]
...but what I'd like to do is loop through all the hosts and get this value from every host, eventually writing this information to my hosts file, but I'd settle for just getting some debug information :)
I tried
...
- debug:
var: hostvars[item].ansible_all_ipv4_addresses[1]
with_inventory_hostnames:
- all
...
...which gives the output I expect, yet when I try to output a msg with this debug task:
...
- debug:
msg: "{{ hostvars[item].ansible_all_ipv4_addresses[1] }}"
with_inventory_hostnames:
- all
...
I get the following error (as I do when I attempt to e.g. write to a file using lineinfile):
fatal: [localhost]: FAILED! =>
msg: |-
The task includes an option with an undefined variable. The error was: 'ansible.vars.hostvars.HostVarsVars object' has no attribute 'ansible_all_ipv4_addresses'
I'm not sure why this is happening, as it's trying to reference the exact same variable. Is there a way to do this?
I've not tested this, but in principle, perhaps this would work?
- hosts: all
- hosts: localhost
gather_facts: false
tasks:
- set_fact:
my_hosts: |
{
{% for a_host in hostvars | dict2items %}
"{{ a_host.key }}": "{{ a_host.value.ansible_all_ipv4_addresses[1] }}",
{% endfor %}
}
Then, instead of looping over hostvars, you just loop over my_hosts?
I have host.yml like this
---
all:
hosts:
server-a:
server_dc: "Hetzner"
ansible_host: 192.168.1.1
server-b:
server_dc: "OVH"
ansible_host: 192.168.1.2
And play book debug is:
- name: sample
debug:
var: hostvars
And all hostvars debug success.
How to get same hostvars variable but filtered. Any of that server_dc is equal OVH
I dont want to iterate for template, i just one new filtered variable that contain all other properies.
I need another variable that i debug see this output:
['server-b']
This I believe meets your requirement (removing 'no_log: true', will result in the complete dictionary being printed in your playbook output):
- set_fact:
filtered_hosts: "{{ filtered_hosts | default({}) | combine({item.key: item.value}) }}"
when: "item.value.server_dc == 'OVH'"
with_dict: "{{ hostvars }}"
no_log: true
- debug:
var: filtered_hosts
Consider the following play. What I am trying to do is add a field, tmp_path which is basically the key and revision appended together to each element in the scripts dict.
---
- hosts: localhost
connection: local
gather_facts: no
vars:
scripts:
a.pl:
revision: 123
b.pl:
revision: 456
tasks:
- with_dict: "{{ scripts }}"
debug:
msg: "{{ item.key }}_{{ item.value.revision }}"
# - with_items: "{{ scripts }}"
# set_fact: {{item.value.tmp_path}}="{{item.key}}_{{item.value.revision}}"
# - with_items: "{{ scripts }}"
# debug:
# msg: "{{ item.value.tmp_path }}"
...
Obviously the commented code doesn't work, any idea how I can get this working? Is it possible to alter the scripts dict directly, or should I somehow be creating a new dict to reference instead?
By the way welcome to correct the terminology for what I am trying to do.
OK, I think I got a solution (below), at least to let me move forwards with this. Disadvantages are it has removed the structure of my dict and also seems a bit redundant having to redefine all the fields and use a new variable, If anyone can provide a better solution I will accept that instead.
---
- hosts: localhost
connection: local
gather_facts: no
vars:
scripts:
a.pl:
revision: 123
b.pl:
revision: 456
tasks:
- with_dict: "{{ scripts }}"
debug:
msg: "{{ item.key }}_{{ item.value.revision }}"
- with_dict: "{{ scripts }}"
set_fact:
new_scripts: "{{ (new_scripts | default([])) + [ {'name': item.key, 'revision': item.value.revision, 'tmp_path': item.key ~ '_' ~ item.value.revision}] }}"
# - debug:
# var: x
# - with_dict: "{{ scripts }}"
- with_items: "{{ new_scripts }}"
debug:
msg: "{{ item.tmp_path }}"
...
BTW credit to the following question which pointed me in the right direction:
Using Ansible set_fact to create a dictionary from register results
Based on this question
Ansible recursive checks in playbooks
I have another one.
We need to go through this structure
Zone spec https://gist.github.com/git001/9230f041aaa34d22ec82eb17d444550c
Now I can adress the hostnames via the array index but can I also iterate over the array "hosts"?
playbook
--
- hosts: all
gather_facts: no
vars_files:
- "../doc/application-zone-spec.yml"
roles:
- { role: ingress_add, customers: "{{ application_zone_spec }}" }
role
- name: Print ingress hostnames
debug: msg="{{ item.hosts.0.hostname }} {{ item.hosts.1.hostname }}"
with_items: "{{ customers.ingress }}"
We use.
ansible-playbook --version
ansible-playbook 2.1.0.0
config file = /etc/ansible/ansible.cfg
configured module search path = Default w/o overrides
Use with_subelements:
- name: Print ingress hostnames
debug: msg="{{ item.0.type }} {{ item.1.hostname }}"
with_subelements:
- "{{ customers.ingress }}"
- "hosts"
There is quite a bit of examples for different loops in the Loops section of the documentation.