Specifications

131
Caveats for Cisco IOS Release 12.0
78-6455-12
Resolved Caveats—Cisco IOS Release 12.0(3)
• CSCdk59879
A Cisco 1600 series router fails when IPSec is configured over an ISDN link. This is caused by the
IP route-cache, which is enabled by default on all interfaces. Disable fast switching on the dialer
interface and the router stops failing. However, TCP packets now get out of order. There is no
workaround.
• CSCdk61860
If the Cisco AS5800 access server router shelf reloads because of a software error, the system might
not discover the dial shelf upon bootup.
Workaround: To recover the system, reload the router shelf manually.
• CSCdk62331
If an ATM permanent virtual circuit (PVC) is deleted on a point-to-point interface and a new PVC
is created, and the new PVC has a different virtual circuit descriptor (VCD) than the old, Cisco
Express Forwarding (CEF) drops packets that should be transmitted on that interface. The interface
configuration commands no pvc followed by pvc produce this behavior, as does the no atm pvc
vcd command followed by the atm pvc different-vcd command.
Workaround: This can be corrected by issuing the shutdown command followed by the
no shutdown command for the affected interface.
• CSCdk62487
When non-distributed CEF is enabled after multicast routing is enabled, multicast packets are
dropped.
Workaround: Disable and then enable multicast routing.
• CSCdk62872
SAR does not see the line pressure properly and overloads the multiplexing chip that causes cell
drops for both UBR and CBR. There is no workaround.
• CSCdk64463
When bridging is configured on an RSM VLAN interface that runs Cisco IOS Release 11.2P or
Cisco IOS Release 11.3, NetFlow or optimum switching does not occur. When bridging is
configured on an RSM VLAN interface that runs Cisco IOS Release 12.0, CEF switching does not
occur. IP packets are processed by fast switching instead of flow/optimum/CEF switching, causing
a significant decrease in the IP packet forwarding rate. The NetFlow Collector might also fail.
There is no workaround.
• CSCdk65706
When you turn off IP routing and reenable IP routing, CEF does not come on by default on some
platforms (for example, the Cisco 12000 [GSR]). There is no workaround.
• CSCdk69045
Custom queuing stops working completely as soon as rate-limit is activated. All queue counters
show zero. Custom queuing can only be restored by reloading the router. There is no workaround.
• CSCdk69355
Enabling tag switching with BGP and a full Internet routing table might cause a Cisco router to
reload. The following message appears:
%SYS-2-CHUNKBADREFCOUNT: Bad chunk reference count, chunk
There is no workaround.