Specifications

85
Caveats for Cisco IOS Release 12.0
78-6455-12
Resolved Caveats—Cisco IOS Release 12.0(6)
• CSCdm30090
When a Cisco router is operating as an X.25 switch, and forwards an X.25 call containing certain
facilities not interpreted by the router, the facility values might be corrupted. The problem occurs
most often when the call cannot be forwarded immediately (for example, when using
X.25-over-TCP) with heavy traffic. The affected facilities include any local facilities and the
Charging Information facility. There is no workaround.
• CSCdm32801
In an NFAS group with a primary and a backup D-channel, fast busies might occur depending on
the failure. If the T1 with the primary D-channel is shut down or fails, and the backup D-channel
comes into service, call routing to a modem in the access server is successful. If the T1 with the
primary D-channel remains in an up condition, but the primary D-channel fails, the backup
D-channel comes into service and call routing fails for B channels on the T1 that contained the
primary D-channel. Users dialing in get fast busies in this scenario. However, calls on all the other
NFAS members, including the T1 with the backup D-channel, are successful. There is no
workaround.
• CSCdm34846
A Cisco router might reload when the ip rtp header-compression command is deconfigured and
encapsulation is changed from PPP to Frame Relay. There is no workaround
• CSCdm36123
A Cisco router might reload with a SegV exception if dialer rotor best is configured, or if deb dialer
is started once traffic triggers a call. There is no workaround.
• CSCdm37653
Reliable PPP can cause intermittent reloads when used with WFQ.
Workaround: Disable Reliable PPP or WFQ.
• CSCdm38291
Dialer watch backup does not dial after the backup interface times out. There is no workaround.
• CSCdm41090
A Cisco 4500 series router might experience a memory leak. When a remote sites go down, or when
an ISDN link drops, the router repeatedly attempts to dial the remote site. If the connection is not
established, the router keeps dialing, eventually runs out of memory, and hangs.
Workaround: Reboot the router.
• CSCdm43734
When dialer watch uses an ISDN connection for the backup link, and the ISDN connection fails to
connect during the connection timeout, and there are multiple dialer maps specifying the
destination IP address corresponding to the watched route, dialer watch fails to retry the secondary
connection, even if the watched route becomes operational and then fails again.
Workaround: Code only a single dialer map command for the secondary interface going to the
watched IP address.
• CSCdm48047
A Cisco 4000 family router might reload if you configure LECS, LES/BUS, and LEC on the router.
There is no workaround.