Recurring Error

In my Mac’s client seafile.log file, i have these recurring log entries:

[07/31/18 15:28:06] sync-mgr.c(574): Repo ‘My Library’ sync state transition from ‘synchronized’ to ‘uploading’.
[07/31/18 15:28:06] http-tx-mgr.c(2302): Upload with HTTP sync protocol version 2.
[07/31/18 15:28:06] http-tx-mgr.c(674): Transfer repo ‘c0c2e66f’: (‘normal’, ‘init’) → (‘normal’, ‘check’)
[07/31/18 15:28:06] http-tx-mgr.c(674): Transfer repo ‘c0c2e66f’: (‘normal’, ‘check’) → (‘normal’, ‘commit’)
[07/31/18 15:28:06] http-tx-mgr.c(674): Transfer repo ‘c0c2e66f’: (‘normal’, ‘commit’) → (‘normal’, ‘fs’)
[07/31/18 15:28:06] http-tx-mgr.c(674): Transfer repo ‘c0c2e66f’: (‘normal’, ‘fs’) → (‘normal’, ‘data’)
[07/31/18 15:28:06] http-tx-mgr.c(2197): Bad response code for PUT https://seafile.domain.com/seafhttp/repo/c0c2e66f-cf7d-45c4-82a3-836c3a4408cb/block/9c8ece0f4ce8ac097f41b4747bee9c92553d0047: 413.
[07/31/18 15:28:06] http-tx-mgr.c(2404): Failed to send block 9c8ece0f4ce8ac097f41b4747bee9c92553d0047 for repo c0c2e66f.
[07/31/18 15:28:06] http-tx-mgr.c(674): Transfer repo ‘c0c2e66f’: (‘normal’, ‘data’) → (‘error’, ‘finished’)
[07/31/18 15:28:06] sync-mgr.c(641): Repo ‘My Library’ sync state transition from uploading to ‘error’: ‘Error occured in upload.’.

How do I go about finding the offending file? Can I delete it to stop whatever “upload” it is trying to do? Maybe followed by restarting the upload, if the file is needed.

The HTTP 413 Payload Too Large response status code indicates that the request entity is larger than limits defined by server; the server might close the connection or return a Retry-After header field.

What web server do you have running on your Seafile server?

I have just migrated the web server to an Nginx docker container.