Which clone() flags isolate hostname, mounts, process IDs, and networking respectively?
clone()
CLONE_NEWPID, CLONE_NEWUTS, CLONE_NEWNET, and CLONE_NEWNS.
CLONE_NEWPID
CLONE_NEWUTS
CLONE_NEWNET
CLONE_NEWNS
No flags are needed because fork() always creates every namespace.
fork()
SIGCHLD alone isolates all four resources.
SIGCHLD
CLONE_NEWUTS, CLONE_NEWNS, CLONE_NEWPID, and CLONE_NEWNET.