Dell S4820T, Configuration Manual

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NOTE: If you are using EqualLogic or Compellent storage arrays, more than 256 simultaneous iSCSI
sessions are possible. However, iSCSI session monitoring is not capable of monitoring more than
256 simultaneous iSCSI sessions. If this number is exceeded, sessions may display as
unknown
in
session monitoring output. Dell Networking recommends that you disable iSCSI session monitoring
for EqualLogic and Compellent storage arrays or for installations with more than 256 simultaneous
iSCSI sessions.
Only sessions the switch observes are learned; sessions flowing through an adjacent switch are not
learned. Session monitoring learns sessions that actually flow through the switch, it does not learn all
sessions in the entire topology.
After a switch is reloaded, any information exchanged during the initial handshake is not available. If the
switch picks up the communication after reloading, it would detect a session was in progress but could
not obtain complete information for it. Any incomplete information of this type would not be available in
the
show
commands.
Detection and Auto-Configuration for Dell EqualLogic Arrays
The iSCSI optimization feature includes auto-provisioning support with the ability to detect directly
connected Dell EqualLogic storage arrays and automatically reconfigure the switch to enhance storage
traffic flows.
The switch uses the link layer discovery protocol (LLDP) to discover Dell EqualLogic devices on the
network. LLDP is enabled by default. For more information about LLDP, refer to
Link Layer Discovery
Protocol (LLDP) .
The following message displays the first time a Dell EqualLogic array is detected and describes the
configuration changes that are automatically performed:
%STKUNIT0-M:CP %IFMGR-5-IFM_ISCSI_AUTO_CONFIG: This switch is being configured
for optimal
conditions to support iSCSI traffic which will cause some automatic
configuration to occur
including jumbo frames and flow-control on all ports; no storm control and
spanning-tree port
fast to be enabled on the port of detection.
The following syslog message is generated the first time an EqualLogic array is detected:
%STKUNIT0-M:CP %LLDP-5-LLDP_EQL_DETECTED: EqualLogic Storage Array detected on
interface Te 1/
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• At the first detection of an EqualLogic array, an MTU of 12000 is enabled on all ports and port-
channels (if it has not already been enabled).
• Spanning-tree portfast is enabled on the interface LLDP identifies.
• Unicast storm control is disabled on the interface LLDP identifies.
Configuring Detection and Ports for Dell Compellent Arrays
To configure a port connected to a Dell Compellent storage array, use the following command.
• Configure a port connected to a Dell Compellent storage array.
INTERFACE Configuration mode
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iSCSI Optimization