BugZero | Cisco BugID CSCuz00344 - ASR901:link flapping for mediatype sfp,with multip...

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BugZero | Cisco BugID CSCuz00344 - ASR901:link flapping for mediatype sfp,with multip...

ODD
Cisco
CSCuz00344

Cisco - Defect ID: CSCuz00344

ASR901:link flapping for mediatype sfp,with multiple shut no shuts

ODD
Cisco
CSCuz00344

Cisco - Defect ID: CSCuz00344

ASR901:link flapping for mediatype sfp,with multiple shut no shuts

Last updated on February 19th, 2026

BugZero Risk Score
6.1 Medium

Overall: 6.1

Severity: 6.4

Lifecycle: 9.1

Popularity: 4.6

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Bug Details

Views: 1

Description

Symptom

Link flaps are seen on 901 when the mediatype is sfp while doing multiple shut no shuts on combo ports.

Conditions

On the image version 901 Software (ASR901-UNIVERSALK9-M), Version 15.5(3)S, the issue is seen. When shut/no shut, link flap, is done on peer device, the port in ASR901 to go to err-disable state or down state. Issue seen on Sumitomo vendor SFPs on combo ports.

Workaround

shut/no shut on the interface/port where the issue is seen.

Further Problem Description

NA

Change history

2026-02-19 Removed: 15.5(3)S

2026-02-19 Removed: 15.5(3)S

2020-06-16 Added: 15.5(3)S

Relevant Products

Click on a version to see all relevant bugs

Affected versions:No known affected versions

Fixed versions: 3.16.3S_V155_3_S3_FC1, 3.16.3aS_V155_3_S3A_FC1, 3.16.4S_V155_3_S4_FC1, 3.16.4aS_V155_3_S4A_FC1, 3.16.4bS_V155_3_S4B_FC1, 3.16.4cS_V155_3_S4C_FC1, 3.16.4dS_V155_3_S4D_FC2, 3.16.4eS_V155_3_S4E_FC1, 3.16.4gS_V155_3_S4G_FC1, 3.16.5S_V155_3_S5_FC2, 3.16.5aS_V155_3_S5A_FC3, 3.16.5bS_V155_3_S5B_FC1, 3.16.6S, 3.16.6bS_V155_3_S6B_FC4, 3.16.7S_V155_3_S7_FC1, 3.16.7aS_V155_3_S7A_FC1, 3.16.7bS_V155_3_S7B_FC1, 3.16.8S_V155_3_S8_FC2, 3.16.9S_V155_3_S9_FC3, 3.17.3S_V156_1_S3_FC2, 3.17.4S_V156_1_S4_FC2, 3.18.0SP_V156_2_SP_FC2, 3.18.0S_V156_2_SP_FC2, 3.18.1SP_V156_2_SP1_FC3, 3.18.1S_V156_2_SP1_FC3, 3.18.1aSP_V156_2_SP1A_FC1, 3.18.1bSP_V156_2_SP1B_FC2, 3.18.1cSP_V156_2_SP1C_FC1, 3.18.1gSP_V156_2_SP1G_FC1, 3.18.1hSP_V156_2_SP1H_FC1, 3.18.1iSP_V156_2_SP1I_FC3, 3.18.2SP_V156_2_SP2_FC2, 3.18.2S_V156_2_SP2_FC2, 3.18.2aSP_V156_2_SP2A_FC3, 3.18.3SP_V156_2_SP3_FC4, 3.18.3S_V156_2_SP3_FC4, 3.18.3aSP_V156_2_SP3A_FC1, 3.18.3bSP_V156_2_SP3B_FC2, 3.18.4SP_V156_2_SP4_FC4, 3.18.4S_V156_2_SP4_FC4, 3.18.5SP_V156_2_SP5_FC4, 3.18.6SP_V156_2_SP6_FC4

Relevant Products

Click on a version to see all relevant bugs

Affected versions:No known affected versions

Fixed versions: 3.16.3S_V155_3_S3_FC1, 3.16.3aS_V155_3_S3A_FC1, 3.16.4S_V155_3_S4_FC1, 3.16.4aS_V155_3_S4A_FC1, 3.16.4bS_V155_3_S4B_FC1, 3.16.4cS_V155_3_S4C_FC1, 3.16.4dS_V155_3_S4D_FC2, 3.16.4eS_V155_3_S4E_FC1, 3.16.4gS_V155_3_S4G_FC1, 3.16.5S_V155_3_S5_FC2, 3.16.5aS_V155_3_S5A_FC3, 3.16.5bS_V155_3_S5B_FC1, 3.16.6S, 3.16.6bS_V155_3_S6B_FC4, 3.16.7S_V155_3_S7_FC1, 3.16.7aS_V155_3_S7A_FC1, 3.16.7bS_V155_3_S7B_FC1, 3.16.8S_V155_3_S8_FC2, 3.16.9S_V155_3_S9_FC3, 3.17.3S_V156_1_S3_FC2, 3.17.4S_V156_1_S4_FC2, 3.18.0SP_V156_2_SP_FC2, 3.18.0S_V156_2_SP_FC2, 3.18.1SP_V156_2_SP1_FC3, 3.18.1S_V156_2_SP1_FC3, 3.18.1aSP_V156_2_SP1A_FC1, 3.18.1bSP_V156_2_SP1B_FC2, 3.18.1cSP_V156_2_SP1C_FC1, 3.18.1gSP_V156_2_SP1G_FC1, 3.18.1hSP_V156_2_SP1H_FC1, 3.18.1iSP_V156_2_SP1I_FC3, 3.18.2SP_V156_2_SP2_FC2, 3.18.2S_V156_2_SP2_FC2, 3.18.2aSP_V156_2_SP2A_FC3, 3.18.3SP_V156_2_SP3_FC4, 3.18.3S_V156_2_SP3_FC4, 3.18.3aSP_V156_2_SP3A_FC1, 3.18.3bSP_V156_2_SP3B_FC2, 3.18.4SP_V156_2_SP4_FC4, 3.18.4S_V156_2_SP4_FC4, 3.18.5SP_V156_2_SP5_FC4, 3.18.6SP_V156_2_SP6_FC4

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