Avaya C360 - Manual (Page 161)

Routing Configuration
Issue 1 July 2006 161
Routing Configuration
Forwarding
The C360 forwards IP packets between IP networks. When it receives an IP packet through one
of its interfaces, it forwards the packet through one of its interfaces. The C360 supports
multinetting, enabling it to forward packets between IP subnets on the same VLAN as well as
between different VLANs. Forwarding is performed through standard means in Router mode.
Multinetting (Multiple Subnets per VLAN)
In Router Mode, most applications such as RIP and OSPF, operate per IP interface. Other
applications such as VRRP and DHCP/BOOTP Relay operate per VLAN. Configuration of these
applications is done in the Interface mode. When there is only a single interface (subnet) per
VLAN then system behavior is intuitive since a subnet and a VLAN are the same.
Multiple interfaces (subnets) per VLAN are more complicated. For example, if there are two
interfaces over the same VLAN and you configure DHCP server on one interface, it will be used
also for the second interface over the same VLAN. This behavior might be less expected and in
some cases wrong.
In order to prevent misconfiguration and unexpected results, the C360 prevents configuration of
VLAN-oriented commands on an interface unless explicitly you specifically request it by the
user via the "enable vlan commands" CLI command.
Configuring the "enable vlan commands" on one interface defeats this option on other
interfaces that belong to the same VLAN. This ensures that VLAN-oriented commands can be
configured from one interface only.
In case there is only one interface over a VLAN, then VLAN oriented commands for this VLAN
can be configured through the single interface without using the "enable vlan commands"
command.
Tip:
Tip:
VLAN-oriented commands that were configured affect the VLAN of the interface
that was used at the time the command was issued.
Tip:
Tip:
If you move the interface another VLAN using the ip vlan CLI command,
VLAN-oriented configuration still relates to the original VLAN.