iPhone Hacked; No Longer Bound to AT&T

George Hotz, along with a team of hackers have come up with a method to break the chains binding the iPhone to AT&T, allowing it to be used with any carrier. The complete method can be found here on George’s blog. It does take some soldering skills and a bit of familiarity with UNIX and modem commands it should be pretty easily accomplished by most techies who have some tinkering under their belts.

Even though I still feel the iPhone is too expensive, and that it is lacking in some basic features, this might just be the thing that gets me to buy one. After all, I love hacking hardware!

I heard an interview with Hots on the way home from work Friday. When asked to respond to internet rumors that former phreaker Steve Jobs was mad at him, he said “I want Steve to call me up. Let’s he and I have a man to man about it.” It was wonderful! If Steve Jobs can’t remember his days hacking the phone system and respect Hots and the team for their accomplishments, he truly has lost touch with what hacking is all about.

Wonderful job guys! Congratulations.

IFCONFIG Does Not give You Link Status; ETHTOOL Does

For some reason that is a complete mystery to me, RHEL does not give you the link status when you run # ifconfig -a. This makes it incredibly hard to debug link integrity issues! Buried amongst all of Red Hat’s proprietary commands, however, is a utility called ethtool, which does give you the status of your link.

Since ethtool is used for querying settings of an ethernet device and changing them, it does a lot more than just give link status. Amongst other things, you can use it to turn on or off autonegotiation on your network card. Run # /sbin/ethtool -h for full usage.

Here’s how you use it to see if your server has link:

# /sbin/ethtool eth0

You should see something like this:

Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full 
                                100baseT/Half 100baseT/Full 
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full 
                                100baseT/Half 100baseT/Full 
        Advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: g
        Wake-on: d
        Link detected: yes

Using Sort to List Directories by Size

If you manage a UNIX system with a large number of directories that vary in size, chances are that you’ve needed to figure out which ones are using up the most disk space. Of course if the directories are user accounts, the best way to do this is to enable quotas and use the “repquota” command. If you just have a bunch of directories, however, you can easily figure out which ones are largest by giving the correct arguments to “du” and “sort”. Here is how:

du -sk * | sort +0nr

This will display the size of all directories and sort them from largest to smallest. If you want to sort them from smallest to largest, simply remove the “r”.

du -sk * | sort +0n

If you have nested directories, you will need to incorporate foreach to recurse through and get all the directory names.