Brocade Virtual ADX Server Load Balancing Guide (Supporting ADX v03.1.00) - Manual (Page 124)

108 Brocade Virtual ADX Server Load Balancing Guide
53-1003247-01
Miscellaneous options
2
Configuring a TCP MSS value at the virtual server port level
The default TCP MSS value configured on a Brocade Virtual ADX is 1460 Bytes. This value can be
changed per virtual server port as shown in the following.
Virtual ADX(config)#server virtual-name-or-ip v1
Virtual ADX(config-vs-v1)#port http tcp-mss 4000
Syntax: [no] port virtual-server-port tcp-mss mss-value
The virtual-server-port variable specifies the TCP port that the MSS value will be applied to.
The mss-value variable specifies the MSS value for all the real server ports bound to the specified
virtual server port. This value can be from 576 to 9176.
Configuring a TCP MSS value at the TCP profile level
The default TCP MSS value configured on a Brocade Virtual ADX is 1460 Bytes. This value can be
changed per TCP profile as shown in the following.
Virtual ADX(config)#tcp profile tcp1
Virtual ADX(config-tcp-profile-tcp1)#tcp-mss 4000
Syntax: [no] tcp-mss mss-value
The mss-value variable specifies the MSS value for all the real servers bound to the specified
virtual server configured with the specific TCP profile. This value can be from 576 to 9176.
Support for TCP Window Scale option in TCP header
The TCP window scale option in TCP header feature optionally increases the definition of the
maximum TCP window from 16 bits (65535) bytes by a window scale factor, to a theoretical
maximum of (8388480 bytes). However, this theoretical value is limited by the maximum RX TCP
buffer size of 3145278 bytes.
If this feature is not enabled, the maximum TCP window remains at 65535 bytes.
The window scale factor is expressed as a shift count - a power of 2. When enabled, the range of
this count is from 1 to 7, i.e., from 2 to the power of 1 to 2 to the power of 7. Zero is the value of the
default shift count, when TCP window scale is not specified
NOTE
The TCP window scale option appears in the SYN segment. Both ends of a TCP connection must send
this option in their SYN segment. Otherwise window scaling is not enabled.