Kopano for Synology in Docker using Debian-9-slim provides packaged binaries via Debian Package Manager repositories from Kopano download area: https://download.kopano.io.
It is customized for Synology in a way MariaDB and Shared Folders are mounted from the NAS device into the container. Note: Docker Pull and Run should NOT be used as this Image is the foundation for a SPK Package available at https://www.cphub.net/?p=kopano4s and will not work isolated..
For the experts insight to get it started: "docker run -d -v /run/mysqld:/run/mysqld:ro -v $K_ETC:/etc/zarafa -v $K_LOG:/var/log/zarafa -v $K_ATC:/var/lib/kopano/attachments $PORTS_EXPOSED --name kopano4s --hostname kopano4s tosoboso/kopano4s: $VER_IN_KOP" would run this image but you have to set the environment which is normally all done by the SPK Package. K_ETC, K_LOG is where you have your kopano-etc and logs outside the container, PORTS_EXPOSED is by default: "-p 236:236 -p 237:237 -p 2003:2003 -p 9080:9080 -p 9443:9443 -p 25:25 -p 1935:1935". K_ATC is where you store attachments if enabled e.g. /volume1/kopano/attachments (optional and not needed to run the kopano4s image). You also have to set pwd in kopano-server.cfg. -In short don't try when you have GUI and SPK Synology Package,