HP AE370A - Brocade 4Gb SAN Switch 4/12, Administrator'S Manual

Page: 328 / 447

328 Administering Extended Fabrics
For dynamic long distance links, you can approximate the number of buffer credits using the following
formula:
Buffer credits = [(distance in km) * (data rate) * 1000] / 2112
The data rate is 1.0625 for 1 Gbit/sec, 2.125 for 2 Gbit/sec, and 4.25 for 4 Gbit/sec and Fibre Channel.
Configuring external ports
The number of ports that can be configured per port group for each switch depends on both port speed
and distance. The following sections specify the number of external ports available for each switch at a
specific port speed and distance.
4/16 SAN Switch and 4/8 SAN Switch
The number of ports that can be configured per port group at various distances is summarized in Table 70 .
SAN Switch 2/8V, SAN Switch 2/16V, SAN Switch 2/32, SAN Director 2/128, and 4/256
SAN Director (FC2-16 port blades)
The number of ports that can be configured per port group at various distances is summarized in Table 71 .
SAN Switch 4/32
The number of ports that can be configured at various distances is summarized in Table 72 .
Table 70 4/16 SAN Switch and 4/8 SAN Switch
Speed
(Gbit/sec) Number of ports allowed at distance (km)
10 km 25 km 50 km 100 km 250 km 500 km
1 16 ports 12 ports 6 ports 3 ports 1 port n/a
2 16 ports 6 ports 3 ports 1 port n/a n/a
4 8 ports 3 ports 1 port 0 n/a n/a
Table 71
SAN Switch 2/8V, SAN Switch 2/16V, SAN Switch 2/32, SAN Director 2/128, and
4/256 SAN Director
Speed
(Gbit/sec)
Number of ports allowed at distance (km)
10 km
25 km 50 km 100 km 250 km 500 km
1 4 ports 4 ports L1 mode: 4
ports
LD mode:
3 ports
up to 2
ports
n/a n/a
2 4 ports 3 ports up to 2
ports
1port n/a n/a
4 n/a n/a n/a n/a n/a n/a
Table 72 SAN Switch 4/32
Speed
(Gbit/sec)
Number of ports allowed at distance (km)
10 km
25 km 50 km 100 km 250 km 500 km
1 32 ports 32 ports 32 ports up to 15
ports
up to 6
ports
up to 3
ports