Discovery Sessions

A discovery session is part of the iSCSI protocol. The discovery session returns the set of targets that you can access on an iSCSI storage system.
systems support dynamic and static discovery.
  • Dynamic discovery - Also known as Send Targets discovery. Each time the
    host contacts a specified iSCSI storage server, it sends a Send Targets request to the server. In response, the iSCSI storage server supplies a list of available targets to the
    host. Monitor and manage with
    esxcli iscsi adapter discovery sendtarget
    or
    vicfg-iscsi
    commands.
  • Static discovery - The
    host does not have to perform discovery. Instead, the
    host uses the IP addresses or domain names and iSCSI target names, IQN or EUI format names, to communicate with the iSCSI target. Monitor and manage with
    esxcli iscsi adapter discovery statictarget
    or
    vicfg-iscsi
    commands.
For either case, you set up target discovery addresses so that the initiator can determine which storage resource on the network is available for access. You can do this setup with dynamic discovery or static discovery. With dynamic discovery, all targets associated with an IP address or host name and the iSCSI name are discovered. With static discovery, you must specify the IP address or host name and the iSCSI name of the target you want to access. The iSCSI HBA must be in the same VLAN as both ports of the iSCSI array.