Allied Telesis AT-9924SP-30, X900-48FE-N, AT-9924T/4SP-A-20 manual Classifiers and Hardware Filters

Classifiers and Hardware Filters

To see details, use the command:

show epsr=test

The following diagram shows the expected output.

--- EPSR Domain Information ---------------------------------------------------
EPSR Domain Name			test
EPSR Domain Node	Type		Transit
EPSR Domain State	.....................		LINKS-UP
MAC Address of Master Node			00:00:CD:24:02:4F
EPSR Domain Status			Enabled
Control Vlan			1000
Ring Interface #	1		5.0
Physical State of Ring Interface # 1.. UP
Ring Interface #	1	Type	UPSTREAM
Ring Interface #	1	State	FORWARDING
Ring Interface #	2		5.1
Physical State of Ring Interface # 2.. UP
Ring Interface #	2	Type	DOWNSTREAM
Ring Interface #	2	State	FORWARDING
Hello Timer (seconds			N/A
Failover Timer (seconds)			N/A
Ringflap Timer (seconds)			N/A
Hello Time Remaining (seconds)			N/A
Failover Time Remaining (seconds)			N/A
Ringflap Time Remaining (seconds)			N/A
Hello Sequence			N/A
Data Vlans			2

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Classifiers and Hardware Filters

On AT-8948, AT-9900, AT-9900s, and x900 series switches, the switching hardware has a limit of 16 bytes to use for matching on incoming packets.

EPSR creates a hardware filter that uses 2 bytes for VLAN identification (since version

291-04). This means that you have to design your network carefully when using EPSR with DHCP snooping, QoS, or other hardware filters.

For example:

•DHCP snooping uses 5 bytes to match on the source and destination UDP ports and the protocol field. With EPSR and DHCP snooping both enabled, 7 out of the 16 bytes are used.

•IP addresses use 4 bytes. So if you configured EPSR, DHCP snooping, and a QoS policy that classified on source IP address, then 11 of the 16 bytes would be used.

Page 29 AlliedWare™ OS How To Note: EPSR