OpenWRT

Years ago, I wrote about using syslog-ng on OpenWRT for logging.

Times have change, and OpenWRT has evolved. With the current stable version (19.07.3), syslog-ng is no longer the preferred method. Instead, I have found that rsyslog works better. In this article, I describe how to install and configure rsyslog.

Now that OpenWRT has released a new stable version: Barrier Breaker 14.07, it was time to upgrade my D-Link DIR-835 router running snapshots to it.

Do do this, I first did the following:

1. Save a list of the packages, using the command:

opkg list-installed

Then using some scripting on the output to ignore the version numbers.

2. Updating the /etc/sysupgrade.conf file to look like this:

/etc/rc.local
/etc/syslog-ng.conf
/etc/crontabs/

On August 12th, I did a presentation on OpenWRT for the KW Linux Users Group.

The slides from this presentation are attached below, and the audio for the presentation is available as a podcast.

Hope it is of use for some.

In that presentation I mentioned wrtbwmon, the bandwidth monitoring script for OpenWRT. You can download my modified version from here.

Years ago, I wrote about the various tools available for monitoring bandwidth usage for individual devices in a home network.

Now, I have a definitive solution that will help with the questions: wrtbwmon. This is based on several variants that are floating around the internet, each a fork of another.

Here is an excerpt from the README file:

Description
===========

If you have a VPS at Linode, then you have free Dynamic DNS. You can use that from a regular Linux machine, or from a router that runs OpenWRT.

This article describes how to setup an OpenWRT router with Linode Dynamic DNS.

First, the script itself, which goes into the file: /etc/custom/linodedns.sh

#!/bin/ash
 
BASE=`basename $0 .sh`
DIR=`dirname $0`

OUTPUT1=/tmp/$BASE-1.out
OUTPUT2=/tmp/$BASE-2.out

# Read the configuration file
CONF=$DIR/$BASE.conf
if [ -r "$CONF" ]; then
  . $CONF
else 

Update 2020-07-09: With the latest 19.07.3, syslog-ng is no longer the preferred option. Instead, read my other article on using rsyslog with OpenWRT.

Update 2014-10-08: If you upgraded to the stable Barrier Breaker 14.07, and Syslog-NG is not available, or if don't want to use Syslog-NG for any other reason, please check our other article on using the built in logging feature of OpenWRT to write the log to a file.

We wrote earlier on OpenWRT on D-Link DIR-835. Now, we need to expand the functionality a bit more.

On OpenWRT, the default logging mechanism is an in-memory circular buffer. The user interface for it is the logread command. The log buffer default size is 16 kB. There are a couple of directives that can be set in the system configuration for OpenWRT, but because of the limited size of flash and the non-permanence of RAM, you need another solution if you want to store logs for anything longer than a day or two.

Syslog-NG

Syslog-NG is a good system logging program that is available for OpenWRT.

This is a quick how to for installing OpenWRT custom firmware on a D-Link DIR-835 router.

Though these instructions were tested on the DIR-835, they apply to many other router models from Linksys, Netgear, ASUS, and many other brands.

Check if your hardware is supported

Update: I have finally found an adequate solution, which is using wrtbwmon, a bandwidth monitoring tool for OpenWRT routers. You can download it from the previous link.

Original article follows ...

Anyone with more than a couple of computers on a LAN will sooner face the issue of increased bandwidth usage by someone on the LAN. Be this teenagers downloading via torrents, employees watching YouTube and Facebook videos, or other reasons.