3Com 10014299 manual Configure the Max age of Bpdu

302CHAPTER 19: CONFIGURING BRIDGE

The Max Age is the parameter used to judge whether the BPDUs are “timeout”. Users can configure it according to the actual network conditions. When a port enables the STP, the Max Age timer begins to time. If no BPDU is received in the specified period, it will assume that the link has failed and the STP will recompute the minimum spanning tree.

Perform the following configuration in system view.

Table 332 Configure the Max age of BPDU

Operation	Command
Configure a time value for the Max Age timer	bridge stp max-age seconds
Restore the default value of the Max Age timer	undo bridge stp max-age

By default, the value of the Max Age timer is 20 seconds. It is in the range of 6 to 40 seconds.

When configuring the Max Age timer, it should be noted that:

■Spanning tree should use the value of the Max Age timer of the root bridge.

■Too short a Max Age will result in frequent recompilations of spanning tree and mistaking the network delay for link fault. On the other hand, too long a Max Age may make the bridge unable to detect link fault promptly and reduce the network self-sensing ability. It is recommended that users use the default value.

6Create ACLs of Bridge

a Create an ACL based on MAC Ethernet addresses Perform the following configuration in system view.

Table 333 Create an ACL based on MAC Ethernet addresses

Operation	Command
Create an ACL based on MAC Ethernet	acl acl-number{ permit deny }
addresses	mac-address mac-wildcard
Delete an ACL based on MAC Ethernet	undo acl acl--number
addresses

By default, no ACL based on MAC Ethernet addresses is created.

When creating an ACL based on MAC Ethernet addresses, value the access-list-numberin the range of 700 to 799. mac-addressis an MAC Ethernet address in the format of xx-xx-xx-xx-xx-xx, which is used to match the source address of a packet. Mac-wildcardis the wildcard of the MAC Ethernet address.

bCreate ACLs based on varied Ethernet encapsulation formats

Perform the following configuration in system view.

Table 334 Create ACLs based on varied Ethernet encapsulation formats

Operation	Command
Create ACLs based on varied Ethernet	acl acl-number{ permit deny }
encapsulation formats	type-code type-wildcard
Delete ACLs based on varied Ethernet	undo acl acl- number
encapsulation formats

By default, no ACL based on varied Ethernet encapsulation formats is created.