Cisco Cisco IOS Software Release 12.0 S
1417
Cross-Platform Release Notes for Cisco IOS Release 12.0S
OL-1617-14 Rev. Q0
Resolved Caveats—Cisco IOS Release 12.0(26)S6
Resolved Caveats—Cisco IOS Release 12.0(26)S6
Cisco IOS Release 12.0(26)S6 is a rebuild of Cisco IOS Release 12.0(26)S. The caveats listed in this
section are resolved in Cisco IOS Release 12.0(26)S6 but may be open in previous Cisco IOS releases.
This section describes only severity 1 and 2 caveats.
section are resolved in Cisco IOS Release 12.0(26)S6 but may be open in previous Cisco IOS releases.
This section describes only severity 1 and 2 caveats.
Interfaces and Bridging
•
CSCef01220
Symptoms: A Versatile Interface Processors (VIP) with a PA-MC-8TE1 port adapter may report its
memory size as unknown even though the VIP appears to function normally, and Distributed
Multicast Fast Switching (DMFS) may fail to function properly.
memory size as unknown even though the VIP appears to function normally, and Distributed
Multicast Fast Switching (DMFS) may fail to function properly.
Conditions: This symptom is observed on a Cisco 7500 series when any of the following conditions
are present:
are present:
–
The mode of the controller of the PA-MC-8TE1 port adapter is not set to T1 or E1 and you insert
or remove another VIP with any port adapter via an OIR.
or remove another VIP with any port adapter via an OIR.
–
Irrespective of whether or not the mode of the controller of the PA-MC-8TE1 port adapter is set
to T1 or E1, you insert or remove a standby RSP via an OIR.
to T1 or E1, you insert or remove a standby RSP via an OIR.
Workaround: Enter the card type {t1 | e1} slot [bay] command on the PA-MC-8TE1+ port adapter
and ensure that none of the controllers on this port adapter are shut down.
and ensure that none of the controllers on this port adapter are shut down.
•
CSCeg03185
Symptoms: A few permanent virtual circuits (PVCs) go into a stuck state causing OutPktDrops on
a Cisco 7200 router.
a Cisco 7200 router.
Conditions: This symptom occurs on a Cisco 7200 router running Cisco IOS Release 12.2(26) with
a PA-A3-T3 ATM interface. The symptom may also occur in other releases.
a PA-A3-T3 ATM interface. The symptom may also occur in other releases.
Workaround: Remove and re-apply the PVC statement.
IP Routing Protocols
•
CSCef60659
A document that describes how the Internet Control Message Protocol (ICMP) could be used to
perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol
(TCP) has been made publicly available. This document has been published through the Internet
Engineering Task Force (IETF) Internet Draft process, and is entitled “ICMP Attacks Against TCP”
(draft-gont-tcpm-icmp-attacks-03.txt).
perform a number of Denial of Service (DoS) attacks against the Transmission Control Protocol
(TCP) has been made publicly available. This document has been published through the Internet
Engineering Task Force (IETF) Internet Draft process, and is entitled “ICMP Attacks Against TCP”
(draft-gont-tcpm-icmp-attacks-03.txt).
These attacks, which only affect sessions terminating or originating on a device itself, can be of
three types:
three types:
1.
Attacks that use ICMP “hard” error messages
2.
Attacks that use ICMP “fragmentation needed and Don’t Fragment (DF) bit set” messages, also
known as Path Maximum Transmission Unit Discovery (PMTUD) attacks
known as Path Maximum Transmission Unit Discovery (PMTUD) attacks
3.
Attacks that use ICMP “source quench” messages
Successful attacks may cause connection resets or reduction of throughput in existing connections,
depending on the attack type.
depending on the attack type.
Multiple Cisco products are affected by the attacks described in this Internet draft.