Infinistream socket table

Summary

In situations that the summary pane of a monitor show data, but drilling down towards the session pane results in "No data available" you might run into overloaded database tables. This article shows how to verify if the Infinistream is suffering from this problem.

Backup configuration

Before proceeding backup the configuration files:

# cp /opt/NetScout/rtm/config/configfile.xml ~/
# cp /opt/NetScout/rtm/bin/configfile ~/

When the task has concluded successfully both files may be deleted from the home folder of user root.

Procedure

Verify if tables are dropping data

Log into the Infinistream and launch a localconsole session:

# isbin
# ./localconsole

Now, enter command-line mode by typing 11 and proceed with the following command:

% get dump tables

Search for the lines skt_trans and skt_table. The last column of these lines show if drops were seen.

Altering the socket table configuration

The first step is altering the file .afm_mode. This file is located in /opt/Netscout/rtm/bin

# isbin
# vi .afm_mode

And append the following line tupple=on

Check the configuration of the socket table:

% get skt

Three parameters can be adjusted:

age interval
table size
tran_count

The default value for age interval is 180 seconds. Reduce the ageout interval in the skt tables (from localconsole CLI) - since modern transactions should be completed very quickly, having an 180-second limit is well beyond the range of what would be considered a "timeout", so having the "ageout" limit of 180-seconds means we store too many entries that should expire from this table. Reducing this ageout value means the table will be cleared faster to allow for more/newer entries to be created.

% set skt 12 age_interval 30

The maximum table size and transaction count depend on the amount of RAM that is installed in the Infinistream. Entering an illegal value will result in a response that informs us about the maximum value for this specific system.

% set skt 12 table a
% set skt 12 tran_count a

Now, the maximum value will become visible on the screen.

As a best practice we will configure 50% of the maximum value returned by "set skt 12 table 5"

For example if the returned value is 32000000, increase the size of the socket table to allow for more traffic:

% set skt 12 table 16000000
% set skt 12 tran_count 16000000

Altering the asr table configuration

In a similar fashion the values of the ASR tables can be adjusted.

First, verify the current settings:

% get xdr

Next, the verify the maximum value that can be configured for that table:

% set xdr 12 sessions a
% set xdr 12 connections a
% set xdr 12 connection_opt a
% set xdr 12 events a

As a best practice we will configure 50% of the maximum value returned by previous command