Configuration Procedures - Foundry Networks Switch and Router Installation And Configuration Manual

Foundry Switch and Router Installation and Configuration Guide
Each client and its server on the other
Foundry device are in the same sub-net.
Traffic between each client and its server
is bridged over a PPP link built on the POS
link on the Layer 2 POS ports.
192.168.1.10
E
C1
192.168.2.10
C2 E
192.168.3.10
E
C3
192.168.4.10
C4 E
Foundry switch A
Figure 6.6 POS Layer 2 port redundancy using a trunk group
This example shows a trunk group configured on a POS module in each chassis. In each module, both POS ports
are configured together as a single link. The links load share and also provide redundancy. If a link in a trunk
group becomes unavailable, the connection is maintained by the other link.
You can use STP with trunk group links. STP regards a trunk group as a single link and thus either forwards or
blocks traffic on all the ports within the trunk group.

Configuration Procedures

To configure a Foundry device for POS Layer 2 switching:
• Change POS interface parameters, if you need to change a parameter from its default value.
• Configure each host sub-net in a separate port-based VLAN.
• Add the POS port as a tagged port to all the host port-based VLANs.
• Optionally, configure redundancy by configuring a second POS port as above, then doing one of the
following:
• Configuring Spanning Tree Protocol (STP) parameters on the ports.
• Adding the POS ports to a trunk group. If you add the ports to a trunk group, the ports load balance
traffic in addition to providing link redundancy.
Configuring a POS Port for Layer 2 Switching
POS ports are configured for Layer 3 IP routing by default. To configure a POS port for Layer 2 switching, you
must add the port as a tagged port to a port-based VLAN.
NOTE: Layer 2 POS ports must be tagged. You cannot add a POS port to a port-based VLAN without tagging
the port.
A POS port is by default a routing-only port. That is, it is by default not a member of the default Layer 2 broadcast
domain (VLAN 1). You can convert a POS port to a Layer-2 switching-only port by adding it to one or more VLANs
as a tagged port. Only traffic from ports belonging to the same VLANs as the tagged POS port are forwarded.
6 - 16
P
O
Fwd
S
Ethernet over POS
P
O
Fwd
S
The POS ports are configured
in a trunk group. The links load
share traffic and also provide
redundancy in case a link
becomes unavailable.
Each client and its server are in their
own port-based VLAN. The VLAN ports
are tagged. The POS ports are configured
in all the client or server VLANs.
P
O
Fwd
S
P
O
Fwd
S
Foundry switch B
192.168.1.20
E
S1
192.168.2.20
E S2
192.168.3.20
E
S3
192.168.4.20
E S4
December 2000