.SAN design reference guide Vol. 1-5 785350-001

Figure 59 Brocade 4Gb SAN Switch for HP c-Class BladeSystem in Access Gateway mode
25318a
Blade enclosure
with 16 servers
Server Bay 16
Server Bay 15
Server Bay 14
Server Bay 13
Server Bay 12
Server Bay 11
Server Bay 10
Server Bay 9
Server Bay 8
Server Bay 7
Server Bay 6
Server Bay 5
Server Bay 4
Server Bay 3
Server Bay 2
Server Bay 1
N_Port (host)
FC switch with
NPIV support
Server
1,2
9,10
3,4
11,12
5,6
13,14
7,8
15,16
Uplink
1
2
3
4
5
6
7
8
Default server to
uplink mapping (2:1)
c-Class BladeSystem
Access Gateway
F_Port (virtual)
Server HBA ports, N_Ports
F_Port (NPIV)
F_Port (NPIV)
F_Port (NPIV)
F_Port (NPIV)
F_Port (NPIV)
F_Port (NPIV)
F_Port (NPIV)
F_Port (NPIV)
N_Port (NPIV)
N_Port (NPIV)
Uplink 2
N_Port (NPIV)
Uplink 3
N_Port (NPIV)
Uplink 4
N_Port (NPIV)
Uplink 5
N_Port (NPIV)
Uplink 6
N_Port (NPIV)
Uplink 7
N_Port (NPIV)
Uplink 8
Uplink 1
c-Class BladeSystem Access Gateway
NOTE: The uplink ports (N_Ports) in Figure 59 (page 171) are from the AG, not the hosts.
Failover policy and failback policy
AG mode supports the failover and failback policies (enabled by default), which you can configure
on a per-port basis.
The failover policy enables automatic remapping of hosts to other online N_Ports if N_Ports go
offline. It evenly distributes hosts among the available N_Ports. This policy ensures a smooth
transition with minimal traffic disruption when a link fails between an N_Port on the AG and an
F_Port on the external fabric.
The failback policy automatically routes hosts back to the original N_Ports when they come online.
NOTE: When a failover or failback occurs, hosts must be logged back in to resume I/O.
AG mode considerations
AG mode considerations follow:
• Ability to connect B-series, C-series, and H-series fabrics without interoperability constraints
(for support information, see the release notes)
• Flexible licensing option (12 or 24 ports, with a 12-port upgrade option on the 12-port model)
• Ability to use in either switch mode or AG mode (cannot function in both modes simultaneously,
software selectable)
• Share Fabric OS with B-series switches
• Port failover between N_Ports (uplinks)
• Reduces the number of cables and SFPs compared to a Pass-Thru solution
BladeSystem with Brocade Access Gateway mode 171