Field Notice: Cisco 7200 IOS ED Release 11.1(14)CA Software Defects

Revised October 2, 1997

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Cisco 7200 IOS ED Release 11.1(14)CA Software Defects

The purpose of this notice is to describe Cisco 7200 IOS ED Release 11.1(14)CA software defects that will be replaced by 11.1(14)CA1.

Cisco Systems, Inc. strives to maintain the highest software quality standards in the internetworking industry. We also seek to provide you, our customers and partners, with the most thorough and advanced software quality information as part of the services available under your Cisco service agreement.

Products Affected

Table 1: Products affected by listed software defects.

Product Series	Issue	Defect
Cisco7200	Only if running SRB or RSRB	CSCdj42984
	Running optimum switching with input access list	CSCdj44697

Problem Description

Note:?If you are a and you have logged in, you can view bug details.

• CSCdj42984 (registered customers only) - Directed SRB Frames have four extra bytes appended

  When source-route bridging between two or more directly attached Token Ring interfaces in a router, Cisco IOS re-calculates and appends a new FCS (CRC) to the end of the old FCS. This results in four extra bytes of "data" being added to the frame's information field.

  CSCdj42984 inhibits certain types of SRB traffic that are sensitive to extra data bytes appended to a frame's information field (for example, IBM SNA sessions fail).

• CSCdj44697 (registered customers only) - Input ACL fast drop on 7200 can cause packet corruption

  If operating a Cisco 7200, configured with optimum switching with input access-list, packets which saw a optimum cache miss and an input access list failure could cause another packet to be corrupted.

Workaround/Solution

Workaround

CSCdj42984:

A possible work around is to disable SRB fast switching with the command no source-bridge route-cache.

Note:?Depending on the amount of network traffic, turning off fast switching may not be a wise workaround.

Another workaround is to downgrade to Cisco IOS ED 11.1(13a)CA1.

CSCdj44697:

No workaround.

Solution

CSCdj42984:

Cisco is working on implementing the fix for CSCdj42984 in Cisco 7200 IOS ED 11.1(14)CA1. The fix will also be placed in Cisco IOS ED 11.2(9)P. Cisco IOS 11.1 and 11.2 mainline are not affected.

CSCdj44697:

Cisco is working on implementing the fix for CSCdj44697 in Cisco 7200 IOS ED 11. 1(14)CA1. Cisco IOS 11.1, 11.2 and 11.2P are not affected.

Table 2: Cisco IOS solution for listed defects

Major Release	Maintenance Release	Images	Defect
11.1CA	11.1(14)CA1	All c7200 images	CSCdj42984, CSCdj44697
11.2M	NA	NA	CSCdj42984, CSCdj44697
11.2P	11.2(9)P	All c7200 images	CSCdj42984
	NA	NA	CSCdj44697

Cisco IOS Versions Affected

Table 3: Cisco IOS affected by listed software defects.

Major Release	Maintenance Release	Images	Defect
11.1CA	11.1(13.3)CA through 11.1(14.1)CA	All c7200 images	CSCdj42984
	11.1(13.5)CA through 11.1(14.2)CA	All c7200 images	CSCdj44697
11.2	NA	NA	CSCdj42984 & CSCdj44697
11.2P	11.2(8.1)P through 11.2(8.5)P	All c7200 images	CSCdj42984
	NA	NA	CSCdj44697

Cisco IOS ED 11.1(14CA1)

Cisco IOS ED 11.1(14)CA1 is pulled from 11.1(14)CA with the following bugs that have been fixed and implemented. Cisco IOS ED 11.1(14)CA1 will replace only the Cisco7200 Series images of 11.1(14)CA.

Note:?If you are a and you have logged in, you can view bug details.

• CSCdj42984 (registered customers only) - Directed SRB Frames have four extra bytes appended

• CSCdj44697 (registered customers only) - Input ACL fast drop on 7200 can cause packet corruption

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

• Open a service request on Cisco.com
• By email
• By telephone

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