Verifying The Isns Server Configuration - Cisco MDS 9000 series Configuration Manual

Chapter 4 Configuring iSCSI
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
On receiving a query request from the iSCSI client, the iSNS server queries the Fibre Channel Name
Server (FCNS) to obtain a list of Fibre Channel targets that are accessible by the querying initiator. The
result of this query depends on zoning configuration currently active and current configuration(s) of the
initiator. The iSNS server will subsequently use the iSCSI target configuration(s) (virtual target and
dynamic import configuration) to translate the Fibre Channel target to an equivalent iSCSI target. At this
stage it also applies any access control configured for the virtual target. A response message with the
target details is then sent back to the query initiator.
The iSNS server sends a consolidated response containing all possible targets and portals to the querying
initiator. For example, if a Fibre Channel target is exported as different iSCSI targets on different IPS
interfaces, the iSNS server will respond with a list of all possible iSCSI targets and portals.
In order to keep the list of targets updated, the iSNS server sends state change notifications (SCN) to the
client whenever an iSCSI target becomes reachable or unreachable. The client is then expected to
rediscover its list of accessible targets by initiating another iSNS query. Reachability of iSCSI targets
changes when any one of the following occurs:
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Verifying the iSNS Server Configuration

Use the show isns config command to view the ESI interval and the summary information about the
iSNS database contents (see
Example 4-25 Displays the iSNS Server Configuration of ESI Interval and Database Contents
switch# show isns config
Server Name: switch1(Cisco Systems) Up since: Fri Jul 30 04:08:16 2004
Use the show isns database command to view detailed information about the contents of the iSNS
database (see
giving all the entities, nodes, and portals registered in the database. This command without options only
displays explicitly registered objects. The asterisk next to the VSAN ID indicates that the iSCSI node
is in the default zone for that VSAN.
Example 4-26 Displays Explicitly Registered Objects
switch# show isns database
Entity Id: dp-204
OL-19525-01,Cisco MDS NX-OS Release 4.2(1)
Target goes up or down.
Dynamic import of FC target configuration changes.
Zone set changes.
Default zone access control changes.
IPS interface state changes.
Initiator configuration change makes the target accessible or inaccessible.
Index: 1 Version: 1
fabric distribute (remote sync): ON
ESI
Non Response Threshold: 5 Interval(seconds): 60
Database contents
Number of Entities: 2
Number of Portals: 3
Number of ISCSI devices: 4
Number of Portal Groups: 0
Example 4-26 through
Index: 2 Last accessed: Fri Jul 30 04:08:46 2004
Example 4-25).
TCP Port: 3205
Example 4-29). This command displays the full iSNS database
Cisco MDS 9000 Family NX-OS IP Services Configuration Guide
iSNS
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