xStack® DGS-3120 Series Layer 3 Managed Gigabit Ethernet Switch Web UI Reference Guide
197
The P-Bit
Also included in the Options field of the LSA type-7 packet, the P-Bit (propagate) is used to define whether or not to
translate the LSA type-7 packet into an LSA type-5 packet for distribution outside the NSSA.
LSA Type-7 Packet Features
•
LSA Type-7 address ranges for OSPF areas are defined as a pair, consisting of an IP address and a mask.
The packet will also state whether or not to advertise and it will also contain an external route tag.
•
The NSSA ASBR will translate external routes into type-7 LSAs to be distributed on the NSSA. NSSA
ABRs will optionally translate these type-7 packets into type-5 packets to be distributed among other OSPF
areas. These type-5 packets are indiscernible from other type-5 packets. The NSSA does not support type-
5 LSAs.
•
Once border routers of the NSSA have finished translating or grouping type-7 LSAs into type-5 LSAs, type-
5 LSAs should be flushed or reset as a translation or an aggregation of other type-7 LSAs.
•
The forwarding addresses contained in translated type-5 LSAs must be set, with the exception of an LSA
address range match.
OSPFv2
OSPF Global Settings
This window is used to configure the OSPF Global settings for this Switch.
To view the following window, click
L3 Features > OSPF > OSPFv2 > OSPF Global Settings
, as shown below:
Figure 5-44 OSPF Global Settings window
The fields that can be configured are described below:
Parameter
Description
OSPF State
Specifies to enable or disable the OSPF global state.
OSPF Router ID
A 32-bit number (in the same format as an IP address - xxx.xxx.xxx.xxx) that uniquely
identifies the Switch in the OSPF domain. It is common to assign the highest IP
address assigned to the Switch (router).
Click the
Apply
button to accept the changes made.
OSPF Area Settings
This window is used to configure the OSPF Area settings for this Switch. OSPF allows collections of contiguous
networks and hosts to be grouped together. Such a group, together with the routers having interfaces to any one of
the included networks, is called an area.
To view the following window, click
L3 Features > OSPF > OSPFv2 > OSPF Area Settings
, as shown below:
Summary of Contents for xStack DGS-3120 Series
Page 1: ......