User Manual

You can configure the switch to monitor traffic for additional port numbers or a combination of port
number and target IP address, and you can remove the well-known port numbers from monitoring.
Information Monitored in iSCSI Traffic Flows
iSCSI optimization examines the following data in packets and uses the data to track the session and
create the classifier entries that enable QoS treatment:
• Initiator’s IP Address
• Target’s IP Address
• ISID (Initiator defined session identifier)
• Initiator’s IQN (iSCSI qualified name)
• Target’s IQN
• Initiator’s TCP Port
• Target’s TCP Port
If no iSCSI traffic is detected for a session during a user-configurable aging period, the session data
clears.
Synchronizing iSCSI Sessions Learned on VLT-Lags with
VLT-Peer
The following behavior occurs during synchronization of iSCSI sessions.
• If the iSCSI login request packet is received on a port belonging to a VLT lag, the information is synced
to the VLT peer and the connection is associated with this interface.
• Additional updates to connections (including aging updates) that are learnt on VLT lag members are
synced to the peer.
• When receiving an iSCSI login request on a non-VLT interface followed by a response from a VLT
interface, the session is not synced since it is initially learnt on a non-VLT interface through the
request packet.
• The peer generates a new connection log that sees the login response packet. If the login response
packet uses the ICL path, it is seen by both the peers, which in turn generate logs for this connection.
iSCSI Optimization: Operation
When the Aggregator auto-configures with iSCSI enabled, the following occurs:
• Link-level flow control is enabled on PFC disabled interfaces.
• iSCSI session snooping is enabled.
• iSCSI LLDP monitoring starts to automatically detect EqualLogic arrays.
iSCSI optimization requires LLDP to be enabled. LLDP is enabled by default when an Aggregator auto-
configures.
The following message displays when you enable iSCSI on a switch and describes the configuration
changes that are automatically performed:
%STKUNIT0-M:CP %IFMGR-5-IFM_ISCSI_ENABLE: iSCSI has been enabled causing flow
control to be enabled on all interfaces. EQL detection and enabling iscsi
profile-compellent on an interface may cause some automatic configurations to
114
iSCSI Optimization