Specifications

Caveats for Cisco IOS Release 12.0

78-6455-12

Resolved Caveats—Cisco IOS Release 12.0(8)

• CSCdm80044

A Cisco router might reload with a bus error in xot_cx_transition. The stack decodes might vary.

There is no workaround.

• CSCdm93360

A Cisco router that is performing X.25 permanent virtual connection (PVC) switching might

experience the following error message if a resend is received on the incoming PVC while the

outgoing PVC is not active:

%X25-3-X25INT: Interface ?, X.25 internal error unable to walk VC output queue

There is no workaround.

• CSCdp00520

The backup interface function does not work if the backup interface is on a 2A/S WAN interface

card network module and is configured with the physical-layer async interface configuration

command. If the primary interface fails, the backup interface will attempt to dial, but it will be

unsuccessful.

Workaround: Use a different network module for the backup interface if you are configuring it

using the physical-layer async interface configuration command. If you are using the 2A/S

network module, and the 2A/S network module is in a lower slot number than the primary interface,

the backup functionality will work.

• CSCdp01840

Excessive CPU utilization might be given to the dialer software component while making multiple

digital calls to an ISDN PRI router. These CPU HOGS will cause a Route Switch Processor with

10 busy PRIs to become unusable. There is no workaround.

• CSCdp02738

Multilink fragments that are sent over an X.25 link might not have an High-Level Data Link Control

(HDLC) header around the PPP packet. This situation can cause the receiving side to be off by 2

bytes when it searches for the protocol of a packet. If the debug ppp {negotiation} EXEC

command has been enabled, you might receive an error message similar to the following:

Vi1 UNKNOWN(0x4000): Non-NCP packet, discarding

There is no workaround.

• CSCdp03096

If a Cisco router with a Versatile Interface Processor (VIP) is running Cisco IOS Release 12.0(6.3),

the VIP might run at 99 percent CPU utilization. This situation occurs when packets are received

on a VIP and should be routed to an interface where the tx-queue-limit is set to a low value like 3.

The VIP will buffer the packets and fail to transfer them to the outbound interface.

Workaround: Configure the tx-queue-limit to a higher value on the outbound interface.

• CSCdp05956

A Cisco 3640 router that is running Cisco IOS Release 12.06(6.3) might reload after running for a

few minutes. There is no workaround.

• CSCdp13681

A Cisco AS5300 universal access server that is running Cisco IOS Release 12.0(6.3)T might reload

with a bus error. There is no workaround.