Router's Subnets - HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual

IP Routing—Configuring RIP, OSPF, BGP, and PBR
Troubleshooting Routing
13-152
An interface only participates in RIP when the network on which it has its
primary address has been added to RIP. You can see which interfaces are
running RIP by viewing the running-config.
The interface may not participate in RIP if the subnet mask for its address has
been entered incorrectly. Make sure that you have entered a subnet mask, not
wildcard bits.
A common problem with RIP is routers using incompatible versions. The
ProCurve Secure Router does not support RIP v2 compatibility mode. This
means that RIP v2 interfaces multicast routing updates. RIP v1 interfaces do
listen for and send multicasts, so the interfaces running different versions do
not receive the routes that they should.
You can also view the RIP version by entering show running-config
router rip.
A particular interface may be configured to override the global version and
send or listen for a different version. View the portion of the running-config
for a particular interface (for example, do show running-config interface
ppp 1) to see what RIP versions it is using. If it is listening for a different type
than that implemented on its network, change it by entering:
ProCurve(config-ppp 1)# ip rip receive version [1 | 2]
If the peer is sending the wrong version type to the local router, you can view
the debug messages (see Table 13-22) to determine which peer is doing so.
However, debug messages can be very processor intensive. You can try
pinpointing the faulty device by the routes the local router is not receiving.
Then, troubleshoot that device.
Routers at remote sites may be separated by a transit network that does not
support multicasts. For example, your organization has established a VPN
through the Internet. In this situation, you must configure a GRE tunnel to
encapsulate routing updates and then tunnel them through the Internet. See
Chapter 9: Configuring a Tunnel with Generic Routing Encapsulation to
learn how to configure this tunnel.
Other Routers Not Receiving Routes to the Local Router's Subnets
A remote router may not receive routes from the local router because:
the local router is sending the wrong version of RIP messages
the local router interface has been configured as a passive interface
connected routes have not been redistributed
the remote router has some problem