3Com SuperStack II 3300 User Manual page 136

136 C 9: P
HAPTER ROBLEM
Table 36 Identifying Problems with the Layer 3 Module (continued)
Problem
If RIP is the routing protocol and
you are using variable length subnet
masks of class A, B or C network
addresses (for example, an address
with a subnet mask of
255.255.255.0 of a Class B
network), your other routers are not
getting correct advertisements for
these networks.
When you try to access those
features of the Layer 3 Module that
do not have their own Web pages,
you get errors mentioning URL.DLL
from the Web interface.
Although you have no front panel
ports up on a VLAN, the ip
interface summary display
reports the corresponding IP
interface as UP. In addition, other
routers are still having routes to that
network advertised to them by the
Layer 3 Module.
You have forgotten your admin
password setting, and therefore
cannot manage your Layer 3
Module.
When you access the Web
interface, you can see the banner
and the tab panel, but nothing in
the Menu tree or workspace.
The fonts in the Web interface are
too small to read easily.
S
OLVING
Cause
Layer 3 Module supports RIP version
1.
RIP version 1 does not support the
advertisement of variable length
subnet masks. It only correctly
advertises unsubnetted class A
(mask 255.0.0.0), class B (mask
255.255.0.0) and class C (mask
255.255.255.0) networks in the
corresponding network ranges.
URL.DLL is used from some Web
browsers to invoke Telnet. If the
URL.DLL is not installed, Telnet does
not work.
Layer 3 Module always reports all of
its IP interfaces as UP. This is
because the Layer 3 Module is (in
effect) directly connected to the
Switch infrastructure through a
tagged-link, and that link to the
Switch fabric never goes down.
Fonts used in the Layer 3 Module
Web pages are configured to be
small in order to include as much
information as possible on each
page.
Solution
Where you have subnets, try one of
the following procedures:
Turn off RIP and define static
routes on your Layer 3 Module
and the other routers to your
subnets.
Use OSPF instead of RIP between
the Layer 3 Module and other
routers.
Only use unsubnetted class A, B
or C network addresses with
your Layer 3 Module.
Run Telnet manually instead.
Follow the procedure in "Resetting
the Module to the Factory Default
Values" in Appendix B, and
reconfigure the Layer 3 Module.
Click the Web Console button on
the tab panel to bring up the menu
tree and workspace.
Reconfigure your browser to
override the document-specified
fonts with your own choice of fonts
and point sizes.