3Com 5500-SI Configuration Manual page 58

58 C 3: P O
HAPTER ORT PERATION
Permitting/Forbidding Jumbo Frames to Pass through an Ethernet Port
An Ethernet port may encounter jumbo frames exceeding the standard frame length,
when switching large throughput data like transmitting files. This command can
forbid or permit jumbo frames to pass through an Ethernet port.
Perform the following configuration in Ethernet Port View.
Table 39 Permitting/Forbidding Jumbo Frame to Pass through the Ethernet Port
Operation
Permit jumbo frame to pass through the Ethernet port
Forbid jumbo frame to pass through the Ethernet port
By default, jumbo frames with lengths between 1518 bytes and 9216 bytes inclusive
are permitted to pass through an Ethernet port.
Setting the Ethernet Port Suppression Ratio
Use the following commands to restrict broadcast/multicast/unicast traffic. Once
traffic exceeds the value set by the user, the system will maintain an appropriate
packet ratio by discarding the overflow traffic, so as to suppress storm, avoid
congestion and ensure the normal service.
Perform the following configuration in Ethernet Port View.
Table 40 Setting the Ethernet Port Suppression Ratio
Operation
Set Ethernet port broadcast
suppression ratio
Restore the default Ethernet port
broadcast suppression ratio
Set Ethernet port multicast
suppression ratio
Restore the default Ethernet port
multicast suppression ratio
Set Ethernet port unicast suppression
ratio
Restore the default Ethernet port
unicast suppression ratio
By default, all traffic is allowed to pass through, that is, no suppression is performed.
Setting the Link Type for an Ethernet Port
An Ethernet port can operate in four different link types: access, hybrid, trunk and stack.
An access port carries one VLAN only, used for connecting to the user's computer. A trunk
port can belong to more than one VLAN and receive/send the packets on multiple VLANs,
used for connection between the Switches. A hybrid port can also carry more than one
VLAN and receive/send the packets on multiple VLANs, used for connecting to both
Switches and the user's computers. The difference between a hybrid port and a trunk port
is that a hybrid port allows the packets from multiple VLANs to be sent without tags, but
a trunk port only allows the packets from the default VLAN to be sent without tags.
Command
jumboframe enable
undo jumboframe enable
Command
broadcast-suppression { ratio | pps
bandwidth }
undo broadcast-suppression
multicast-suppression { ratio | pps
bandwidth }
undo multicast-suppression
unicast-suppression { ratio | pps
bandwidth }
undo unicast-suppression