Red Hat Bugzilla – Bug 149846
RHEL4: Add filtering for duplicate entries in netstat
Last modified: 2015-01-07 19:09:28 EST
+++ This bug was initially created as a clone of Bug #139407 +++ Description of problem: Client is experiencing duplicate entries in the output of netstat such as the following: netstat -a |grep piics2 tcp 0 0 hqias4:mtflocal piics2:33135 ESTABLISHED tcp 0 0 hqias4:mtflocal piics2:33135 ESTABLISHED The read() call on the /proc filesystem is, as Ben put it, best effort. That means that they try to make the data consistent, but it isn't always. The result is that sometimes two read() calls in /proc/net/tcp will return the same entry because the kernel shuffles the table around in between the read() calls, causing the duplicate entries that are reported in the bug. Version-Release number of selected component (if applicable): net-tools-1.60-19.AS21.1 How reproducible: Problem occurs randomly, but with considerable frequency. Steps to Reproduce: 1. run netstat -a 2. observe duplicate entries (identical lines) 3. Actual results: some lines may be displayed twice Expected results: no duplicate entries Additional info: This came from Morgan Stanley.
Errata created
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2005-242.html