user95678: I am updating my RaspiBolt according to this guide. Unfortunately, the guide changed a lot since my last update. It is still great, though!
I am upgrading from v0.8.10 to v0.9.3 and somewhere in between the path for electrs config changed to /data/electrs/electrs.conf.
Where was it before?

user95678: I found the old config with systemctl edit --full-edit electrs.service in the line
ExecStart=/usr/local/bin/electrs --conf /mnt/bitcoin/electrs/electrs.conf.
The location of the config changed because the guide introduced a different setup for the data storage. In the old setup user bitcoin was necessary. This user is now deactivated for interaction and just used by the bitcoin service. Data is now stored in /data which is owned by bitcoin:bitcoin and the user admin is in the group bitcoin, making changes possible with user admin.
I was wondering why /data is not mounted from the external SSD/HDD. Reason is the guide now suggests to run the whole operating system from the SSD.
Other important notes for updating electrs can be found here. Although it is not stated as necessary, using the old verbose = option in the config did result in a failed startup. I had to just use log_filters =.
Also, I had to update bitcoin.conf with whitelist=download@127.0.0.1 so that electrs can get a connection.

95678: <p>I am updating my RaspiBolt according to this <a href="https://raspibolt.org/electrs.html" rel="nofollow noreferrer">guide</a>. Unfortunately, the guide changed a lot since my last update. It is still great, though!</p>
<p>I am upgrading from <code>v0.8.10</code> to <code>v0.9.3</code> and somewhere in between the path for <code>electrs</code> config changed to <code>/data/electrs/electrs.conf</code>.</p>
<p>Where was it before?</p>
 95678: <p>I found the old config with <code>systemctl edit --full-edit electrs.service</code> in the line</p>
<p><code>ExecStart=/usr/local/bin/electrs --conf /mnt/bitcoin/electrs/electrs.conf</code>.</p>
<p>The location of the config changed because the guide introduced a different <a href="https://raspibolt.org/system-configuration.html#data-directory" rel="nofollow noreferrer">setup</a> for the data storage. In the old setup user <code>bitcoin</code> was necessary. This user is now deactivated for interaction and just used by the bitcoin service. Data is now stored in <code>/data</code> which is owned by <code>bitcoin:bitcoin</code> and the user <code>admin</code> is in the group <code>bitcoin</code>, making changes possible with user <code>admin</code>.</p>
<p>I was wondering why <code>/data</code> is not mounted from the external SSD/HDD. Reason is the guide now suggests to run the whole operating system from the SSD.</p>
<p>Other important notes for updating <code>electrs</code> can be found <a href="https://github.com/romanz/electrs/blob/master/doc/upgrading.md" rel="nofollow noreferrer">here</a>. Although it is not stated as necessary, using the old <code>verbose =</code> option in the config did result in a failed startup. I had to just use <code>log_filters =</code>.</p>
<p>Also, I had to update <code>bitcoin.conf</code> with <code>whitelist=download@127.0.0.1</code> so that <code>electrs</code> can get a connection.</p>
