Two copies of each file when using three clouds

[leiva]

What is the problem you are having with rclone?

Hi, I've been looking through the documentation but I can't find anything. Let's say I have three clouds: Company1, Company2 and Company3, with 10GB, 20GB and 30GB respectively. What I want to know is if it's possible to use rclone to treat these three as a single cloud while keeping only two copies of each file in two different clouds. I know it's possible to copy each file to all three clouds but I can't find out if it's possible to do just two copies. Any ideas? I'm new to rclone.

Run the command 'rclone version' and share the full output of the command.

rclone v1.73.0
- os/version: arch (64 bit)
- os/kernel: 6.12 (x86_64)
- os/type: linux
- os/arch: amd64
- go/version: go1.25.6 X:nodwarf5
- go/linking: dynamic
- go/tags: none

Which cloud storage system are you using? (eg Google Drive)

I want to use mostly webdav remotes.

Please run 'rclone config redacted' and share the full output. If you get command not found, please make sure to update rclone.

; empty config

[rclone-ui]

Rclone doesn't have a built‑in 2-out-of-3 replication mode.

However, you can unify several remotes into one namespace with the union backend, and you can replicate every file to all of them (using create_policy = all ), but there’s no native policy to write only to two out of three.

My idea is to configure a union remote that joins all three clouds, but tag one cloud as :ro (read‑only):

[company1]
type = webdav
url = https://company1.example.com/webdav
…

[company2]
type = webdav
url = https://company2.example.com/webdav
…

[company3]
type = webdav
url = https://company3.example.com/webdav
…

[multicloud]
type = union
upstreams = company1: company2: company3:ro
create_policy = all
action_policy = all
search_policy = ff

Here company3 is marked :ro, so new writes will only go to company1 and company2. Union’s policies will then put every file on those two writable remotes (skipping the read‑only one). The union backend still shows a single combined view (multicloud:) of all three, but each file physically resides only on two of them. The default search_policy=ff (“first found”) means reads use whichever copy the union finds first, and with action_policy=all any rename or delete in the union is applied to all existing copies.

The third cloud (company3 here) becomes effectively unused for writes, wasting its capacity. Also, if company3 had preexisting data, new writes won’t reach it. In short, you get a unified mount and automatic 2‑copy writes, but one cloud is sidelined (marked read‑only) by design.