Simon R has written and asked about extending the ideas raised by my how-to article, “Network Flow Rates”, published in September 2004’s Australian Macworld article,. He’d like to use MRTG to monitor a couple of Airport Express base stations. Specifically he’d like to be able to monitor his broadband usage, and Airtunes streams.
Now I don’t have any experience with the new Airport Express yet (if someone would like to donate or loan me one for a while I can certainly document my discoveries!) however I have used SNMP with the original graphite Airport and today I had a play with a couple of the latest model Airport Extreme basestations.
There is an official Airport Extreme MIB available from Apple here. It should work with any Airport basestation running v5.1 or above. (It may indeed work with earlier models as well) A MIB file provides you with easier to use nouns allowing you to request various information available from the device via SNMP – without having to use more cumbersome OIDS (object identifiers). Presently it would appear that the information available from a Airport via SNMP is about the physical ethernet interface(s), and information about each of the connected wifi clients including MAC (media access control) addresses, number of packets in and out per second, the number of errors, signal strength, and DHCP records if it is running DHCP. There’s nothing in there about AirTunes but there is a comment that they intend to provide an interface to information about the USB port, connected printers and more network details at some point in the future. It’s fair to assume that Apple will provide an interface for Airtunes as well – or someone else will figure out how to access it.
Reg F has brought to my attention a serious typo in my how-to article “Set up your own DNS: Master your domain” published in the August 2004 issue of Australian Macworld. On page 61 in the bottom left-hand paragraph I have written
sudo pico /usr/sbin/named
where I should have written
sudo pico /etc/named.conf
Afterall the goal was supposed to be configuring named not modifying the binary itself.
As you can no doubt see – this is a bad, bad thing – as, if you follow my instructions you will destroy your named binary and will be seeing errors like
sudo: unable to exec /usr/sbin/named: Bad CPU type in executable
when you try to start it.
*yikes* what was I thinking when I typed that?
Anywho, if you’ve trashed your named binary, the only thing you can really do at this point is replace it with a new one. As the OS X installer doesn’t provide you with a way to do this short of reinstalling the entire operating system I’m going to provide a link to a pristine copy. I don’t think there should be any legal issue with me doing this as Apple freely provides the source code for their port of bind here. However if you know of an issue send me an email and I will take down the links.
- If you have Mac OS X 10.3 use this link
- If you have Mac OS X 10.2 use this link
To replace your busted named type:
cd /usr/sbin; sudo tar zxvf ~/Desktop/named-9.2.2.tar.gz
(provided of course that you’ve downloaded the above link to your Desktop).
I sincerely appologise for any inconvenience I may have caused anyone who followed my published instruction. I promise to proof read my article more closely in future
[edit 12:58am 10/8/2004 - added link for named 8.3.4 for Jaguar]
Don F contacted me about a problem he was having after following my how-to article “Share an internet connection with OS X:The Scenic Route” published in May 2004 issue of Australian Macworld.
Don had purchased an additional ethernet card for his Mac in order to share his broadband connection with other computers in his house. However while the other machines appeared to be being configured correctly they were unable to see the Internet
It turns out that he also had the personal Firewall enabled (in Sharing in System Preferences) and this was interfering with the sharing function. Disabling the firewall appears to allow sharing to work again.
Obviously switching off the firewall is not the best solution to Don’s problem but I don’t have an alternative for him at this time
I will continue to investigate this matter
