Cisco Cisco IOS Software Release 12.2 Release Notes

When you upgrade from Cisco IOS Release 12.1(4)DA or earlier to Release 12.2(12)DA2, the default 
soft PVC addresses on all interfaces change. This occurs only when you upgrade to Release 
12.2(12)DA2 from Release 12.1(4)DA or earlier.

Workarounds:

Reconfigure the soft PVCs associated with all interfaces.

Assign a (nondefault) address to the interfaces.

If you wish to use a Cisco router for an IDSL application and the router is running a Cisco IOS release 
earlier than Release 12.1, you must configure the ISDN switch type. If you do not configure the ISDN 
switch type on the Cisco router, the router’s BRI interface might not come back up after the IDSL line 
goes down and comes back up.

To prevent this problem from occurring, execute the isdn switch-type basic-ni command in global 
configuration mode on the router.

This problem does not occur if the Cisco router is running Cisco IOS Release 12.1 or later.

This release supports the full range of VPI values: 0 to 255. However, if you configure VP tunnels with 
traffic shaping, you can use only 32 VPIs out of that range. If you have not yet assigned any VPIs, all 
values from 0 to 255 are available. Once you start assigning VPIs, however, the assigned VPIs limit the 
VPIs that remain. (You assign VPIs using the atm pvp or atm pvc command.)

After a particular VPI value is assigned to a shaped VP tunnel, every 32nd VPI value above and below 
the first one is eliminated—that is, the original value modulo 32. For example, if you assign VPI 94 to 
a shaped VP tunnel, the following VPI values become unavailable for any purpose: 30, 62, 126, 158, 190, 
and 222.

To avoid problems, choose a block of 32 consecutive VPI values (for example, 0 to 31 or 101 to 132). 
The software rejects invalid VPI values.

You can install multiple Cisco 6160 DSLAMs in a Telco equipment rack. A standard 7-foot equipment 
rack can house four Cisco 6160 DSLAMs, stacked one on top of another. This configuration maximizes 
the DSL density within a 7-foot rack. However, if space is available or you are interested in using any 
multiservice capabilities that the DSLAM might support in the future, we recommend that you install no 
more than three Cisco 6160 DSLAMs in a 7-foot rack. Leave a space of at least 2.5 rack units 
(4.375 inches, or 11.1 cm) beneath each DSLAM for future cable management use.