I am currently taking two hosts and dynamically adding them to a group, followed by a synchronize
task using with_together
to use 3 lists of 2 elements in parallel to copy the specified files between two remote servers.
Here's an example based on the idea:
---
- name: Configure Hosts for Copying
hosts: localhost
gather_facts: no
tasks:
- name: Adding given hosts to new group...
add_host:
name: "{{ item }}"
groups: copy_group
with_items:
- ["remoteDest1", "remoteDest2"]
- name: Copy Files between servers
hosts: copy_group
gather_facts: no
tasks:
- name: Copying files...
synchronize:
src: "{{ item[1] }}"
dest: "{{ item[2] }}"
with_together:
- ["remoteSrc1", "remoteSrc2"]
- ["/tmp/remote/source/one/", "/tmp/remote/source/two/"]
- ["/tmp/remote/dest/one/", "/tmp/remote/dest/two/"]
delegate_to: "{{ item[0] }}"
Currently, it does both operations for both servers, resulting in 4 operations.
I need it to synchronize like so:
/tmp/remote/source/one/
from remoteSrc1
to /tmp/remote/dest/one/
on remoteDest1
/tmp/remote/source/two/
from remoteSrc2
to /tmp/remote/dest/two/
on remoteDest2
Which would mean it's a 1:1 ratio; essentially acting on the hosts in the same manner as with_together
does for the lists.
The hosts are obtained dynamically, so I can't just make a different play for each host.
Since synchronize
is essentially simplified version of rsync
, then if there's a simple solution for this using rsync
directly, then it would be much appreciated.
There isn't native functionality for this, so this is how I solved it:
Given the original task, add the following two lines:
- "{{ groups['copy_group'] }}"
when: inventory_hostname == item[3]
To get:
- name: Copying files...
synchronize:
src: "{{ item[1] }}"
dest: "{{ item[2] }}"
with_together:
- ["remoteSrc1", "remoteSrc2"]
- ["/tmp/remote/source/one/", "/tmp/remote/source/two/"]
- ["/tmp/remote/dest/one/", "/tmp/remote/dest/two/"]
- "{{ groups['copy_group'] }}"
delegate_to: "{{ item[0] }}"
when: inventory_hostname == item[3]
Essentially, by adding the hosts as a list, they can be used in the when
statement to execute the task only when the current host (inventory_hostname
) matches the host currently being indexed in the list.
The result is that the play only runs against each host once in a serial manner with the other list items that have the same index.