ftp and tftp uid

[Kathy Solomon]

/etc/passwd currently contains:

ftp:*:500:1:Anonymous FTP user:/home/ftp:/usr/bin/false
tftp:*:510:1:Trivial FTP user:/home/tftpdir:/usr/bin/false

Is it practical to change the uid for these accounts or are 500 & 510 carved in stone?

[Pupil_1]

Yes they can be changed.

[A. Clay Stephenson]

Nothing is special about them but you should change /home/ftp and /home/tftpdir to refect the new UID. Files and directories don't care about login names but rather about UID's and GID's.

[Kathy Solomon]

Other than not stomping on a uid already taken, are there any guidelines for changing these uids?

e.g. Do services need to be restarted or server rebooted?

[A. Clay Stephenson · Accepted solution]

Because both of these are started by inetd, existing connections would use the old values and new connections would use the new values. However, because changing the UID/GID of these directories while current connections are established, permission problems could occur. Thus the safe approach would be to comment out the ftp/tftp inetd.conf entries; run inetd -c; and wait until all ftp connections are finished. Make your changes to the uid's and directories, uncomment the inetd.conf entries, and "inetd -c". Declare victory.