GRASS VALLEY K2 SAN, Installation And Service Manual

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K2 client media (iSCSI) connection failover behavior
K2 RAID
K2 Media
Servers
K2 SAN-attached system
Ethernet
switches
A
A
B
B
Fibre Channel
connections
Control
Media
Control
Media
Control
FTP
Media
Control
FTP
Media
ISLs
X
Connection
Failure
Control traffic goes
to server A, which is
still the media file
system/database
server.
iSCSI traffic uses
the iSCSI adapter
on server B.
If the following system connection or component fails to respond to network communication:
• Media (iSCSI) network “A” connection between a K2 SAN-attached system and the GigE switch
Then the following failover behavior occurs:
1. The K2 SAN-attached system drops communication on its “A” media port and begins using its
“B” media port and the “B” media (iSCSI) network. The iSCSI adapter (TOE) on the “B” K2
Media Server provides access to the Fibre Channel connected RAID storage.
2. Control traffic keeps using the same path to K2 Media Server “A”.
3. K2 Media Server “A” is still the media file system/metadata server. The media file system (SNFS)
and media database do not fail over.
4. The other K2 SAN-attached systems (not affected by the component failure) keep using the same
paths for media and control, as in pre-failover behavior. This means the K2 SAN-attached systems
unaffected by the failover are using the iSCSI adapter (TOE) on the “A” K2 Media Server to
provide access to the Fibre Channel connected RAID storage, while at the same time the affected
K2 SAN-attached systems are using the iSCSI adapter (TOE) on the “B” K2 Media Server to
provide access to the Fibre Channel connected RAID storage. In this case both RAID controller
are simultaneously providing disk access.
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Operating the K2 SAN