Avaya Media Gateway G350, Maintenance Manual

Page: 281 / 332

Monitoring
Extended keepalive
Maintenance of the Avaya G350 Media Gateway 281
June 2004
Figure 22: G350 with T1 and xDSL lines
For example, your branch office may have a G350 that connects to the Headquarters over a T1 line and
via an xDSL connection to the Internet. The T1 line is used for voice traffic, while data packets are sent
over the xDSL line. Normal keepalive cannot report on the status of the entire WAN path. If the
FastEthernet line protocol is up but the xDSL connected to it is down, normal keepalive reports that the
FastEthernet interface is up. Only Extended Keepalive, which checks the next hop, correctly reports that
the WAN path is down. Policy-based-routing, which relies on the interface status to determine how
packets are routed, can use Extended Keepalive to know the status of the interfaces on its next hop list.
NOTE:
Extended Keepalive is not used with a GRE tunnel interface. The GRE tunnel has its own
keepalive mechanism. For details, refer to Administration of the Avaya G350 Media
Gateway, 555-245-501.
Configuring extended keepalive
You configure Extended Keepalive by enabling the mechanism on an interface and configuring its
settings.
Enabling extended keepalive
Use the keepalive command to enable Extended Keepalive on an interface. In the context of the
interface, run the keepalive command and specify the destination IP address.
For example, to enable Extended Keepalive on the FastEthernet interface for destination IP address
192.31.1.175, enter the following commands:
G350-001# interface FastEthernet 10/2
G350-001(if:FastEthernet 10/2)# keepalive 192.31.1.175
2 x T1/E1 or USP WAN Module
Small Branch
Hub/Switch
S8300
xDSL1
ISP
Data
Vlan2
DSCP
Voice
Vlan1
DSCP
G350
Headquarters
T1
T1
Router
GRE Tunnel