Instruction manual

Chapter 2 Installation, Configuration and Management
2-80 NetScaler 9000 Series Installation and Configuration Guide - Volume 1
NSICG60_DEC04
Table 2-1 Conditions and Behavior of the NetScaler System on Receipt of a PMTU
related ICMP Error
2.7.3 Configuring PMTU Discovery
z For enabling the Path MTU Discovery mode, use the following CLI
command:
enable ns mode PMTUD
z For disabling the Path MTU Discovery mode, use the following CLI
command:
disable ns mode PMTUD
No. Condition
Behavior of the NetScaler
System
1 When the NetScaler system is in
the MIP mode of operation.
Passing the ICMP error to the
server will have the server adjust
the MTU to the NetScaler MIP.
This will affect all the clients
using the same MIP to that
particular server. Hence, the
ICMP error is consumed by the
NetScaler system and the MTU
database is updated. All packets
sent out on that connection
would have the DF bit unset. All
new connections will use the
MTU value from the database.
2 When the NetScaler system is in
the USIP mode of operation, and
an ICMP error message is
received.
The ICMP error message is
translated and sent to the server.
The server updates the MTU for
the destination and subsequent
datagrams go out with a lowered
MTU. The MTU value for that
client is also updated in the
NetScaler system. All new
connections use the lowered
MTU value.