issues with haproxy + nginx + fpm - need some help debugging this

[rmalchow]

hi,

i have a nextcloud instance running behind a pfsense haproxy:

[client] -- https --> [haproxy] -- http --> [nginx] -- fpm --> [nextcloud]

and i am seeing stalled uploads and this:

Error | no app in context | 
Sabre\DAV\Exception\BadRequest: Expected  filesize of 1724803 bytes but read (from Nextcloud client) and wrote  (to Nextcloud storage) 40960 bytes. Could either be a network problem on  the sending side or a problem writing to the storage on the server  side.
/var/www/html/apps/dav/lib/Connector/Sabre/Directory.php - line 156: 
OCA\DAV\Connector\Sabre\File->put(null)
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 1098: 
OCA\DAV\Connector\Sabre\Directory->createFile(" --- filename --- ", null)
/var/www/html/3rdparty/sabre/dav/lib/DAV/CorePlugin.php - line 504: 
Sabre\DAV\Server->createFile(" --- filename --- ", null, null)
/var/www/html/3rdparty/sabre/event/lib/WildcardEmitterTrait.php - line 89: 
Sabre\DAV\CorePlugin->httpPut(Sabre\HTTP\Request {}, Sabre\HTTP\Response {})
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 472: 
Sabre\DAV\Server->emit("method:PUT", [ Sabre\HTTP ... }])
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 253: 
Sabre\DAV\Server->invokeMethod(Sabre\HTTP\Request {}, Sabre\HTTP\Response {})
/var/www/html/3rdparty/sabre/dav/lib/DAV/Server.php - line 321: Sabre\DAV\Server->start()
/var/www/html/apps/dav/appinfo/v1/webdav.php - line 84: 
Sabre\DAV\Server->exec()/var/www/html/remote.php - line 167: require_once("/var/www/ht ... p")
-- | -- | --

the only combination of settings that i have found to work thus far is smaller chunks (<32k) and "option forceclose" in haproxy. i am pretty sure something is going wrong in between haproxy and nginx, and i am assuming something along the lines of a mismatch between size in header size in body - but i am not entirely sure how to approach debugging this.