Unison does not support syncing between two different versions. Hence, syncing across different ubuntu releases this problem will necessarily occur unless they contain many unison versions in the future.
Workaround: 1) On both machines delete the unison cache: rm -r ~/.unison 2) Make sure no version of unison is installed on the machine with the newer Ubuntu release. 3) On the machine with the newer Ubuntu release download the unison .deb file of the older release. For example the .deb file of the unison version of Ubuntu 18.04 can be found here: https://ubuntu.pkgs.org/18.04/ubuntu-universe- amd64/unison_2.48.4-1ubuntu1_amd64.deb.html Install this unison version via the graphical interface. 4) On the machine with the newer Ubuntu release freeze the unison version you just installed. Warning you will not get security updates! sudo apt-mark hold unison 5) Sync both machines using unison. Have fun! -- You received this bug notification because you are a member of Debian OCaml Maintainers, which is subscribed to unison in Ubuntu. https://bugs.launchpad.net/bugs/1868502 Title: Synchronization with earlier Ubuntu versions or a recent Debian version fails Status in unison package in Ubuntu: Confirmed Bug description: Any synchronization I want to do with my server (Debian buster) fails with the following message: > Fatal error: Server: Fatal error during unmarshaling (input_value: ill-formed message), > possibly because client and server have been compiled with differentversions of the OCaml compiler. Indeed, buster uses OCaml 4.05.0, focal uses 4.08.1. eoan used 4.05.0, as did the prior versions, including bionic, which all still synchronize fine. The current Windows version also synchronizes with that version. Although intentionally using an old software version for compatibility is not a good thing, in this case it might be necessary. The whole point of unison is its interoperability. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unison/+bug/1868502/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ocaml-maint Post to : [email protected] Unsubscribe : https://launchpad.net/~ocaml-maint More help : https://help.launchpad.net/ListHelp
