I found my old reMarkable 2 paper tablet, bought in 2021, it had sat unused for ~4 years or so. The device was in a sorry state:
This post details how you might be able to bring your tablet back to working order if you find yourself in a similar situation.
Googling the error I found a forum post with what its author called “the fast solution”, SSH in, set the clock:
After setting the time, I was able to download a software update.
After the first software update, cloud sync now gave me a different error:HTTP 400. I found the actual error message in the journal:“Unable to sync. Please update this application to continue using the reMarkable cloud.”
The cloud was rejecting my obsolete system version. Turns out the first update only brought the tablet to3.11.2.5and wouldn’t update further.
journalctlforswupdate.serviceshowedCouldn’t resolve host name(after the post-update reboot, the updater had started before wifi/DNS was up and never retried). Restarting the update services made the Settings screen offer3.27.3.0, and a second update brought the tablet to the latest available software version.
Starting with version 3.22 of the software,SSH over wifi is now silently disabledby the update, so port 22 refuses on the LAN.
SSH in to the tablet via USB (e.g.10.11.99.1) instead. Re-enable network SSH withrm-ssh-over-wlan on, or drop the marker filerm_enable_ssh_wifi_marker(thedropbear-wlan.socketunit is already enabled, just inactive)
For whatever reason, cloud sync still appeared to be broken, it wouldn’t pull any of my new uploads.
Instead of debugging this further (by now I was done dealing with the cloud sync), I found that the table has an optional web server that can be turned on, to allow you to upload and export files from the device. I backed up the xochitl config before toggling it on (WebInterfaceEnabled=true):