USERMOD(8) (System Management Commands) (NAME) usermod - (SYNOPSIS) usermod [] LOGIN (DESCRIPTION) usermod . (OPTIONS) usermod : -a, --append () . -G . -b, --badname . -c, --comment COMMENT (comment) /etc/passwd chfn(1) . -d, --home HOME_DIR . -m . . -e, --expiredate EXPIRE_DATE . YYYY-MM-DD . 1970-01-01 . -1 shadow . . /etc/shadow . /etc/shadow . -f, --inactive INACTIVE . shadow . 0 . -1 shadow . shadow(5) . /etc/shadow . /etc/shadow . -g, --gid GROUP (ID) . . . . uid . / . -G, --groups GROUP1[,GROUP2,...[,GROUPN]]] . . . . -a . -l, --login NEW_LOGIN LOGIN NEW_LOGIN . . (mail spool) . -L, --lock . '!' . -p -U . : ( ) EXPIRE_DATE 1 . -m, --move-home . . -d ( --home) . usermod (modes) ACL . -o, --non-unique . -u . UID . -p, --password PASSWORD . PASSWORD crypt (3) . : ( ) . /etc/passwd /etc/shadow . PAM . . -r, --remove () . -G . -R, --root CHROOT_DIR CHROOT_DIR CHROOT_DIR. . -P, --prefix PREFIX_DIR PREFIX_DIR . chroot (cross-compilation) . : / NIS LDAP . PAM . SELINUX . -s, --shell SHELL . SHELL /etc/passwd . -u, --uid UID . -o . . . . uid . / . UID_MIN UID_MAX SYS_UID_MIN SYS_UID_MAX /etc/login.defs . -U, --unlock . '!' . -p -L . : ( ) EXPIRE_DATE ( 99999 EXPIRE /etc/default/useradd). -v, --add-subuids FIRST-LAST uid (subordinate uids) . . SUB_UID_MIN SUB_UID_MAX SUB_UID_COUNT /etc/login.defs . -V, --del-subuids FIRST-LAST uid . . --del-subuids --add-subuids uid uid . SUB_UID_MIN SUB_UID_MAX SUB_UID_COUNT /etc/login.defs . -w, --add-subgids FIRST-LAST gid (subordinate gids) . . SUB_GID_MIN SUB_GID_MAX SUB_GID_COUNT /etc/login.defs . -W, --del-subgids FIRST-LAST gid . . --del-subgids --add-subgids gid gid . SUB_GID_MIN SUB_GID_MAX SUB_GID_COUNT /etc/login.defs . -Z, --selinux-user SEUSER SELinux LOGIN. ("") ( ) . shadow selinux-user semanage(8) . (CAVEATS) . usermod . utmp . crontab at . NIS NIS . (CONFIGURATION) /etc/login.defs : LASTLOG_UID_MAX (number) lastlog . (sparse) lastlog . LASTLOG_UID_MAX lastlog . MAIL_DIR (string) (mail spool). . . CREATE_MAIL_SPOOL /etc/default/useradd . MAIL_FILE (string) . MAIL_DIR MAIL_FILE useradd usermod userdel . MAX_MEMBERS_PER_GROUP (number) . ( ) /etc/group ( GID). 0 . ( ) . NIS . 25 . : ( Shadow). . SUB_GID_MIN (number), SUB_GID_MAX (number), SUB_GID_COUNT (number) /etc/subuid useradd newusers ( ) SUB_GID_COUNT SUB_GID_MIN SUB_GID_MAX . SUB_GID_MIN SUB_GID_MAX SUB_GID_COUNT . SUB_UID_MIN (number), SUB_UID_MAX (number), SUB_UID_COUNT (number) /etc/subuid useradd newusers ( ) SUB_UID_COUNT SUB_UID_MIN SUB_UID_MAX . SUB_UID_MIN SUB_UID_MAX SUB_UID_COUNT . (FILES) /etc/group /etc/gshadow . /etc/login.defs Shadow /etc/passwd /etc/shadow /etc/subgid /etc/subuid (SEE ALSO) chfn(1), chsh(1), passwd(1), crypt(3), gpasswd(8), groupadd(8), groupdel(8), groupmod(8), login.defs(5), subgid(5), subuid(5), useradd(8), userdel(8). shadow-utils 4.13 12/14/2025 USERMOD(8)