@JQ,

Hi,

Glad to hear the first part worked!

For your second SSD, you can simply add another root entry in the work.prf file. Unison allows multiple roots, but each pair must refer to one sync job. Meaning: each work.prf can only define two roots at a time.

So you’ll need a separate profile for the second SSD.

For example, keep your existing work.prf as-is, then create another profile like work-kingsto.prf:

root = /home/jq/Downloads
root = "/run/media/jq/128 KINGSTO"

auto = true
batch = true
prefer = newer

Now you’ll run it like:

unison work-kingsto

This keeps both sync setups clean and avoids conflicts.

Dear Ravi Saive,

This solved the problem:

root = "/run/media/jq/128 WESTERN"

But what if I want to sync to another SSD? There are two SSDs in the external case, how should I configure that?

Here is my current work.prf:

root = /home/jq/Downloads
root = "/run/media/jq/128 WESTERN"

auto = true
batch = true
prefer = newer

I have another SSD mounted at /run/media/jq/128 KINGSTO in the same external case. How do I add it to work.prf?

Thanks.

@JQ,

Thanks for sharing the details. From the error message, it looks like Unison is trying to create a temporary directory on /run/media/jq/128 WESTERN, but it doesn’t have permission to do so.

A few things to check:

1. Make sure your user (jq) has write permissions on the mount point /run/media/jq/128 WESTERN. You can test this by trying to create a folder manually:

mkdir /run/media/jq/128\ WESTERN/test

If this fails, it’s a permissions issue.

2. If it’s a removable drive or a mounted partition, ensure it’s mounted with write permissions (sometimes drives are mounted read-only by default).

3. You might also want to remove the backslash from the profile path and quote the path instead:

root = "/run/media/jq/128 WESTERN"

Unison handles spaces better with quotes in profile files.

Try these steps and see if it resolves the issue.

Hi Ravi,

The following command works fine:

unison ~/Downloads /run/media/jq/128\ WESTERN

However, when I try to automate the job by creating a work profile, I encounter an error. Details are as follows:

Profile (work.prf):

root = /home/jq/Downloads
root = /run/media/jq/128\ WESTERN

auto = true
batch = true
prefer = newer

When I run the command:

jq@fedora:~$ unison work

I get the following output:

Unison 2.53.7 (ocaml 5.3.0): Contacting server...
Looking for changes
Reconciling changes
new dir  ---->              

1 items will be synced, 0 skipped
45.9 MiB to be synced from Downloads to 128\ WESTERN
0 B to be synced from 128\ WESTERN to Downloads
Propagating updates
Unison 2.53.7 (ocaml 5.3.0) started propagating changes at 09:14:51.85 on 16 Oct 2025
[BGN] Copying from /home/jq/Downloads to /run/media/jq/128\ WESTERN
Failed []: Error in creating directory:
Permission denied [mkdir(/run/media/jq/.unison.128\ WESTERN.823146198a581844c627fe0871e557fe.unison.tmp)]
Unison 2.53.7 (ocaml 5.3.0) finished propagating changes at 09:14:51.85 on 16 Oct 2025, 0.000 s
Saving synchronizer state
Synchronization incomplete at 09:14:51 (0 items transferred, 0 skipped, 1 failed)
  failed: 
jq@fedora:~$

I’d appreciate your help in resolving this.

Thanks,

@JQ,

Looks like the issue is with the paths you’re using in your Unison command. You don’t need to include /home/jq twice — Unison is interpreting that as a profile name instead of a folder.

Try this command instead:

unison ~/Downloads /run/media/jq/128\ WESTERN

A few quick notes:

The backslash (\) before the space in 128 WESTERN escapes the space so the system reads it correctly.

You don’t need the ~/home/jq/ prefix — just ~/Downloads works fine.

Make sure both directories actually exist and your external SSD is mounted.

If this runs without errors, Unison should start syncing your Downloads folder to the SSD.

Hope that helps!