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B.2. iSCSI Disks During Start Up

Events related to iSCSI might occur at a number of points while the system is starting:
  1. The init script in the initrd will log into iSCSI targets used for /, if any. This is done using the iscsistart utility, without requiring iscsid to run.

    Note

    If the root file system is on an iSCSI disk connected using IPv6, ensure that the installed system is using the correct ip= boot option, for example ip=eth0:auto6. If this option is not set, the installed system can spend up to 20 minutes at boot time attempting to establish a connection, before eventually succeeding. Using the correct ip= option eliminates this delay.
  2. When the root file system has been mounted and the various service init scripts are running, the iscsi init script will get called. This script then starts the iscsid daemon if any iSCSI targets are used for /, or if any targets in the iSCSI database are marked to be logged into automatically.
  3. After the classic network service script has been run, the iscsi init script will run. If the network is accessible, this will log into any targets in the iSCSI database that are marked to be logged into automatically. If the network is not accessible, this script will exit quietly.
  4. When using NetworkManager to access the network, instead of the classic network service script, NetworkManager will call the iscsi init script. Also see the /etc/NetworkManager/dispatcher.d/04-iscsi file for further reference.

    Important

    Because NetworkManager is installed in the /usr directory, you cannot use it to configure network access if /usr is on network-attached storage such as an iSCSI target.
If iscsid is not needed as the system starts, it will not start automatically. If you start iscsiadm, iscsiadm will start iscsid in turn.