The WebDAV-Server (Apache2) was updated 14 days ago and the sync procedure on all devices ran without any issues.
Only the iPad produces errors since yesterday.
To check if all connection parms are ok I modified
the url
the username
both to false contents, restart DTTG, correct them and restart DTTG again.
After that the syncing process start without error messages. In the protocol I can see that DTTG is syncing now in both directions.
The problems mentioned above seem to be related to the connection parameters.
I often switch from DTTG to other apps. If there are too many open at the same time, I cancel them.
Could it therefore be that the problems are related to the background task of DTTG and that this may damage the connection parameters directly or indirectly ?
Now I’m just waiting to see if the sync process finishes properly.
Actually this error is only triggered if the server doesn’t return valid XML (e.g. if the WebDAV server is not running at all or if the URL is not the one of the WebDAV server).
Creating and using a new sync location?
And post an unredacted screen capture of DEVONthink’s Settings > Sync. If you don’t want to post it here, hold the Option key in DEVONthink and choose Help > Report bug to start a support ticket.
I have now been able to solve the problem:
the last OS update on the iPad obviously activated the switch „/Wi-Fi/I (information button behind your selected Wi-Fi)/Limit IP Address Tracking“.
If addionally in the connection parameters of DDTG „domain.name“ was stored in URL, the sync was then always done via the Internet and not via internal LAN.
Normally that causes no problem but I had a smooth misconfiguration in my proxy which of course only came into effect when there was external access.
After fixing this, syncing is now possible on the iPad at all communication channels.
If the switch mentioned above is set, it is still surprising that Apple always accesses the Internet without querying the internal DNS servers!
If it is switched off, however, all access to the database are (really) much faster.
Maybe there is another library for DTTG that could be linked and that always initially carries out the queries via the internal DNS servers ?
Nevertheless however … thanks for your support !