> Hi, > > we are upgrading some servers from C6 to C7 with a lot of user accounts > on them (UID>=500). > CentOS 7 has MIN_UID/MIN_GID 1000, Centos 6 has 500 in login.defs. > > Can I change in /etc/login.defs MIN_UID/MIN_GID to 500 for C7? So I > could just grep the users out from passwd/shadow/group files and append > them to the Centos7 passwd/shadow/group files. > Can this do any damage to CentOS7 later on? Thinking about updates.... When I did an upgrade from CentOS 5 to 7 I found that even a standard install of CentOS 7 already used a number of GIDs in the range of 500-999. In the end I decided to rearrange all users to new UIDs/GIDs and converted all storage with a script. The tricky part was to find a way which doesn't take ages to convert storage. Doing so with find.... wasn't possible for performance reasons. Attached script was used to convert every user. It was the fastest way I found. The script was started in background for every user. Regards, Simon