Isns Cloud Discovery; About Cloud Discovery - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Chapter 50 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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iSNS Cloud Discovery

You can configure iSNS cloud discovery to automate the process of discovering iSNS servers in the IP
network.
This section includes the following topics:
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About Cloud Discovery

Note iSNS Cloud Discovery is not supported on the Cisco Fabric Switch for IBM BladeCenter and Cisco
Fabric Switch for HP c-Class BladeSystem.
When an iSNS server receives a query request, it responds with a list of available targets and the portals
through which the initiator can reach the target. The IP network configuration outside the MDS switch
may result in only a subset of Gigabit Ethernet interfaces being reachable from the initiator. To ensure
that the set of portals returned to the initiator is reachable, the iSNS server needs to know the set of
Gigabit Ethernet interfaces that are reachable from a given initiator.
OL-17256-03, Cisco MDS NX-OS Release 4.x
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.
About Cloud Discovery, page 50-73
Configuring iSNS Cloud Discovery, page 50-74
Cisco MDS 9000 Family Fabric Manager Configuration Guide
iSNS Cloud Discovery
50-73