On an auth failure the uid and the IP address should be logged to the standard log file.   This update works for a standard setup, when using a proxy for the server one can probably use the X-forwarded-for header   instead of the remote address.
On an auth failure the uid and the IP address should be logged to the standard log file.
  This update works for a standard setup, when using a proxy for the server one can probably use the X-forwarded-for header
  instead of the remote address.

pixelipo/server,endsguy/server,IljaN/core,sharidas/core,Ardinis/server,pixelipo/server,jbicha/server,andreas-p/nextcloud-server,whitekiba/server,michaelletzgus/nextcloud-server,xx621998xx/server,nextcloud/server,bluelml/core,sharidas/core,owncloud/core,owncloud/core,nextcloud/server,Ardinis/server,xx621998xx/server,cernbox/core,pmattern/server,pollopolea/core,IljaN/core,lrytz/core,bluelml/core,lrytz/core,lrytz/core,Ardinis/server,michaelletzgus/nextcloud-server,IljaN/core,lrytz/core,pmattern/server,lrytz/core,owncloud/core,jbicha/server,endsguy/server,pollopolea/core,owncloud/core,bluelml/core,xx621998xx/server,whitekiba/server,sharidas/core,endsguy/server,IljaN/core,nextcloud/server,endsguy/server,andreas-p/nextcloud-server,cernbox/core,pmattern/server,jbicha/server,bluelml/core,jbicha/server,whitekiba/server,cernbox/core,pixelipo/server,Ardinis/server,cernbox/core,sharidas/core,endsguy/server,andreas-p/nextcloud-server,sharidas/core,Ardinis/server,jbicha/server,andreas-p/nextcloud-server,nextcloud/server,pollopolea/core,pmattern/server,michaelletzgus/nextcloud-server,andreas-p/nextcloud-server,whitekiba/server,pollopolea/core,phil-davis/core,pollopolea/core,owncloud/core,cernbox/core,pmattern/server,pixelipo/server,xx621998xx/server,pixelipo/server,whitekiba/server,bluelml/core,michaelletzgus/nextcloud-server,IljaN/core,xx621998xx/server