A "Tail" logging terminal session may occasionally hang and cannot be exited

Technical Articles ID: KB84480
Last Modified: 5/21/2020

Environment

McAfee VirusScan Enterprise for Linux (VSEL) 2.0, 2.0.1, 2.0.2

All supported Linux operating systems

Problem

A terminal session to "Tail" a live log file generated by an application occasionally stops working and cannot be exited using CTRL+C. When this occurs, that particular session can be exited only after you disable the VSEL On-Access Scanner, or stop the nails service (with the command /etc/init.d/nails stop).

Cause

McAfee has determined that the issue is actually in the Fanotify feature of Linux Kernels when multiple threads iterate to the same directory or files. This can result in some threads hanging.

McAfee has opened the following Bug Report with Kernel.org: https://bugzilla.kernel.org/show_bug.cgi?id=95131.

Solution

This issue is not directly related to or caused by VSEL. Any future solution must come from the Kernel and development teams for the Linux operating systems involved. If you experience this issue, McAfee recommends that you contact support for the operating system manufacturer.

Until the manufacturers resolve the issue, you can use the following workaround.

Workaround

Use the following commands to run tail or tailf with output buffering disabled:

#unbuffer tail –f /dir/logfile

#unbuffer tailf –n /dir/logfile

Related Information

Related issue caused by the same issue in Fanotify:
KB85826 - IBM DB2 backup session halts and hangs at 99% when VirusScan Enterprise for Linux 2.0.x On-Access Scanner is enabled

Affected Products

Known Issue/Product Defect
VirusScan Enterprise for Linux 2.0.x

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A "Tail" logging terminal session may occasionally hang and cannot be exited

Environment

Problem

Cause

Solution

Workaround

Related Information

Affected Products

Languages:

Glossary of Technical Terms

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Knowledge Center

A "Tail" logging terminal session may occasionally hang and cannot be exited

Environment

Problem

Cause

Solution

Workaround

Related Information

Affected Products

Languages:

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