NAME

       nbdkit-service - how to mount NBD filesystems on a client machine

DESCRIPTION

       For NBD exports that contain filesystems there are several approaches to mounting them on
       a client machine.

       To ensure the nbd kernel module is loaded you may need to do:

        # echo nbd > /etc/modules-load.d/nbd.conf

       This will not take effect until you reboot, so also do:

        # modprobe nbd

   Easy mounting at boot time
       For simple setups the following method is the easiest way to get an NBD filesystem to
       mount at boot.  Create or edit /etc/rc.local or /etc/rc.d/rc.local:

        #!/bin/sh -
        nm-online
        modprobe nbd
        nbd-client server /dev/nbd0
        mount /dev/nbd0 /mnt

   Mounting using systemd mount points
       You can use systemd mount points to mount NBD filesystems at boot and/or on demand.

       Set up an nbdtab(5) mapping.  If /etc/nbdtab doesn't exist, then create it first.  Add
       this line:

        nbd0 server / bs=512,persist

       As a workaround for https://github.com/NetworkBlockDevice/nbd/issues/91 you must currently
       modify the nbd@.service file:

        # cp /usr/lib/systemd/system/nbd@.service /etc/systemd/system/
        # vi /etc/systemd/system/nbd@.service

       and edit or create these settings in the "[Service]" section:

        [Service]
        Type=oneshot
        RemainAfterExit=yes
        ExecStart=/usr/sbin/nbd-client %i
        ExecStop=/usr/sbin/nbd-client -d /dev/%i

       Finally create a systemd mount file called /etc/systemd/system/mnt.mount:

        [Unit]
        Requires=nbd@nbd0.service
        [Mount]
        What=/dev/nbd0
        Where=/mnt
        Type=ext4

       You can either reboot now or do:

        # systemctl start mnt.mount

       Other systemd services which need this mount point can depend on this mount unit.

SEE ALSO

       nbdkit(1), nbdkit-loop(1), nbdkit-service(1), nbd-client(8), nbdtab(5), systemd(1),
       systemd.mount(5).

AUTHORS

       Richard W.M. Jones

COPYRIGHT

       Copyright (C) 2013-2020 Red Hat Inc.

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