Frequent freezes with strange errors in the log

[lahwaacz]

We have an instance of Nextcloud with CollaboraOnline running in Docker containers. It worked fine for some time, but since today CollaboraOnline frequently freezes with the following errors in the log. Do you know what is the problem?

wsd-00015-00015 2020-04-15 11:16:09.940978 [ loolwsd ] TRC  Have 1 new children.| wsd/LOOLWSD.cpp:3443
wsd-00015-00015 2020-04-15 11:16:09.941080 [ loolwsd ] INF  WSD initialization complete: setting log-level to [warning] as configured.| wsd/LOOLWSD.cpp:3450
wsd-00015-00021 2020-04-15 11:16:09.958494 [ websrv_poll ] ERR  Socket #21 SSL BIO error: closed unexpectedly (-1). (0: Success)| ./net/SslSocket.hpp:278
wsd-00015-00021 2020-04-15 11:16:09.958662 [ websrv_poll ] ERR  Error while handling poll for socket #21 in websrv_poll: SSL Socket closed unexpectedly.| ./net/Socket.hpp:594
wsd-00015-00021 2020-04-15 11:16:25.451839 [ websrv_poll ] WRN  client - server version mismatch, disabling browser cache. Expected: f7d232d75| wsd/FileServer.cpp:279
wsd-00015-00021 2020-04-15 11:16:26.131440 [ websrv_poll ] WRN  FileServerRequestHandler: File not found: Invalid URI request: [/loleaflet/f7d232d75/branding.css].| wsd/FileServer.cpp:440
wsd-00015-00021 2020-04-15 11:16:26.144621 [ websrv_poll ] WRN  FileServerRequestHandler: File not found: Invalid URI request: [/loleaflet/f7d232d75/branding.js].| wsd/FileServer.cpp:440
wsd-00015-00021 2020-04-15 11:17:44.053410 [ websrv_poll ] WRN  client - server version mismatch, disabling browser cache. Expected: f7d232d75| wsd/FileServer.cpp:279
wsd-00015-00021 2020-04-15 11:17:44.726436 [ websrv_poll ] WRN  FileServerRequestHandler: File not found: Invalid URI request: [/loleaflet/f7d232d75/branding.css].| wsd/FileServer.cpp:440
wsd-00015-00021 2020-04-15 11:17:44.740413 [ websrv_poll ] WRN  FileServerRequestHandler: File not found: Invalid URI request: [/loleaflet/f7d232d75/branding.js].| wsd/FileServer.cpp:440
wsd-00015-00021 2020-04-15 11:17:44.846038 [ websrv_poll ] WRN  DocBroker with docKey [/index.php/apps/richdocuments/wopi/files/417_ocq9gz77f5ll] that is marked to be destroyed. Rejecting client request.| wsd/LOOLWSD.cpp:1733
wsd-00015-00021 2020-04-15 11:17:44.846373 [ websrv_poll ] ERR  Error while handling Client WS Request: Failed to create DocBroker with docKey [/index.php/apps/richdocuments/wopi/files/417_ocq9gz77f5ll].| wsd/LOOLWSD.cpp:2918
wsd-00015-00021 2020-04-15 11:17:44.846436 [ websrv_poll ] ERR  #21: attempted to remove: 1323 which is > size: 0 clamped to 0| ./net/Socket.hpp:972
wsd-00015-00021 2020-04-15 11:17:44.846497 [ websrv_poll ] ERR  Socket #21 SSL BIO error: error:1420C0CF:SSL routines:ssl_write_internal:protocol is shutdown (0: Success)| ./net/SslSocket.hpp:291
wsd-00015-00021 2020-04-15 11:17:44.846600 [ websrv_poll ] ERR  Error while handling poll for socket #21 in websrv_poll: error:1420C0CF:SSL routines:ssl_write_internal:protocol is shutdown| ./net/Socket.hpp:594