Field Notice: FN - 64197 - WAAS Devices That Run 6.1.1, 6.1.1a, or 6.2.1 Might Have Connections Reset - Software Fix Available

Available Languages

Updated:September 1, 2016

Document ID:FN64197

Bias-Free Language

The documentation set for this product strives to use bias-free language. For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. Learn more about how Cisco is using Inclusive Language.

NOTICE:

THIS FIELD NOTICE IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTY OF MERCHANTABILITY. YOUR USE OF THE INFORMATION ON THE FIELD NOTICE OR MATERIALS LINKED FROM THE FIELD NOTICE IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS FIELD NOTICE AT ANY TIME.

Revision History

Revision	Date	Comment
1.0	01-SEP-2016	Initial Public Release

Products Affected

Products Affected	Comments
WAAS - Software Versions 6.1.1, 6.1.1a, 6.2.1	All WAAS platforms- Physical appliances and virtual WAAS

Problem Description

After six to eight weeks of system uptime, Cisco Wide Area Application Services (WAAS) devices that run Software Version 6.1.1, 6.1.1a, or 6.2.1 start to retransmit packets quickly between peers. Due to issues with the timer scheduler, timers misfire before their scheduled times. This results in immediate retransmissions of TCP packets and might cause connection resets.

When this condition is triggered, traffic on the WAN increases. Not all connections might fail during this condition, but this can cause a network outage.

Background

6.1.1, 6.1.1a, and 6.2.1 WAAS software timer scheduler compares the current and scheduled times and incorrectly determines that all the scheduled timers have elapsed. All the timers are then executed without delay.

Problem Symptoms

Access to WAAS devices will be very slow due to the access link congested by the fast retransmission of the packets. Central Manager will report optimized traffic volume much greater than the original traffic.

Workaround/Solution

In order to correct this issue, complete these steps:

Reboot the WAAS devices - the problem will likely recur after a similar time has elapsed.
Upgrade to WAAS 6.2.1a or later (recommended). WAAS software can be found on the WAAS Download Software page.

CDETS

To follow the bug ID link below and see detailed bug information, you must be a registered customer and you must be logged in.

CDETS	Description
CSCva30228 (registered customers only)	WAAS cons are retransmitting packets very quickly and are getting reset

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:

Receive Email Notification For New Field Notices

Cisco Notification Service—Set up a profile to receive email updates about reliability, safety, network security, and end-of-sale issues for the Cisco products you specify.