Tag Archives: tutorial

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EDIT: Tonight i’ll be picking up one of my Mac Mini’s from the Datacenter to get Ubuntu 13.04 up and running! expect a full guide with drivers here shortly :)

So Ubuntu 13.04 LTS recently was released, It comes with the new 3.8.0-19 upstream of the Linux Kernel so I thought I’d check it out!

Although our patched 12.04 and 12.10 Ubuntu’s use version 3.124c of the tg3 NeXtreme drivers from Broadcom which have Mac Mini support… The version in Ubuntu 13.04 (3.128c) seems to have had this removed!

A simple run of modinfo tg3 | grep 1686 reveals sadly that support for detection of the Mac Mini Ethernet hardware seems to have been removed during 3.124 and 3.128 of the Broadcom tg3 drivers.

I’m likely to install 13.04 on a Mac Mini sometime soon so will update this post with a proper howto and any good news I encounter but I don’t think its good news…

lsmod | grep Ethernet returns
01:00.0 Ethernet controller: Broadcom Corporation Device 1686 (rev 01)

whilst modinfo tg3 | grep 1686 on our modified 12.04/12.10 machines using the NeXtreme driver from this blog returns:

alias:          pci:v000014E4d00001686sv*sd*bc*sc*i*

however on 13.04 returns nothing.

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Just a quick post to say i’ve posted my first piece of code in over 5 years to GitHub. Its a clever little Objective-C iOS Category on UIViewController that seemlessly overlays a UILabel on every single view controller managed view with the class, nib or storyboard name that is used. Great for debugging old or inherited projects with minefield architectures. It uses some cool libobjc runtime techniques to accomplish this, but implementing the category is a case of dropping it into your project and Build+Go!

Category in Action

Grab the source code here as usual, follow me @italoarmstrong on twitter :)

 

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My Raspberry PI

Out the box the Raspberry PI comes with a ARM1176JZFS Core (armv6 with hard float aka armhf arch) running at 700 Mhz as part of the Broadcom SoC. Additionally the memory frequency is also limited. In recent firmwares however… tinkerers have had the ability to “overclock” the Raspberry PI to squeeze some extra juice out of it. Mine’s currently running at 1Ghz at a solid 48C temperature when under load. So the first question that springs to mind is… why doesn’t everyone overclock their Raspberry PI? Well… there have been (well founded) reports of SD card corruption, heat/power issues and instability. The idea of this post is to show the user how to safety squeeze every last bit, cycle and IOP out of their PI safely’ish and without being an astrophysicist. Read on for the know-how. Continue reading →

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So in the last post I discussed why the Mac Mini is the perfect machine for Linux and for Datacenters in general! One frustration some readers may be finding is that the networking chipset used by Ivy Bridge platform in Late 2012 Mac Mini’s doesn’t have native support in the Linux Kernel (as of now anyway). So its required to install a kernel module from the manufacturer/vendor (broadcom).

On their website they provide the “tg3″ drivers for Linux kernels, however these are only good if you are running a Linux kernel < 3.5.x. If you take Ubuntu for example, 12.04 uses the 3.2.x stream, whereas 12.10 uses the 3.5.x stream and isn’t immediately compatible with the drivers on the broadcom page. This is due to the deprecation in 3.x and removal in 3.5.x of the asm/system.h header.

Read on for the fix, more and downloads. Continue reading →

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So… some of you may have already seen this, if you didn’t then, here it is :) its pretty cool, it works… but has one caveat… Its a TEMPORARY unlock… i.e. it will unlock your phone sure, but once your TMSI (Temporary Mobile Subscriber Identity) is refreshed, you will have to repeat the process again… in the UK and US i think this happens when you switch the phone on/off or travel over a large geographic area… however it could potentially happen whenever…

Instructions on how to unlock are after the break :)

  1. Grab your iPhone
  2. Insert a supported Sim Card… so, if your phone is locked to Tmobile, put a Tmobile sim in there Continue reading →
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Many people already know that the Samsung green drives have a bug in the firmware that may cause data loss, Samsung have created a patch that you need to create a bootable floppy disk along and drag in their file, if like me you don’t have a floppy disk drive & don’t want to mess around with USB booting and creation of a drive or just cannot boot from USB then you’ll need another solution, i’ve put together a quick bootable CDROM ISO that contains freedos and the patch, simply boot and type F4EG and hit enter, the patch will automatically detect your drives and update them. I hope this helps people out as it did me. As quoted from the original site:

“If identify commmand is issued from host during NCQ write command in the condition of PC ,
write condition is unstable.
So It can make the loss of written data.”
(Model : F4EG HD204UI, HD204UI/Z4, HD204UI/UZ4, HD155UI, HD155UI/Z4, HD155UI/UZ4)

Samsung Article regarding firmware and affected drives

CaptainGeek Bootable ISO: DOWNLOAD

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Well, i’ve used FreeNAS for around 2 years+ now, and all has been good, however, in that time demand for large quantities of storage has now been joined by demand for high speed storage; Once I had replaced all of my drives with 2tb 7200rpm drives I realised that FreeNAS wasn’t giving me the performance on each drive that i’d like.

Welcome NexentaStor… a storage appliance natively supporting ZFS as its based on OpenSolaris! NexentaStor offers many of the same features of FreeNAS, however at a greater level of performance. This comes at a cost though, the free Community edition is limited to a some what large 18tb, whereas the paid version will cost you.

Also NexentaStor is a pure storage appliance, although it supports CIFS/iSCSI/NFS and the likes, it does not have all the bells and whistles of FreeNAS… but for me, there is no use having all these features if I can’t have the speed.

I’m installing NexentaStor now as we speak, after which I’ll be posting a review / tutorial on NexentaStor after i’ve got it up and running and configured to my liking :) I hope you enjoy it!

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Hi everyone! I keep getting lots of emails from people asking where they can buy xyz to complete the tutorials and try out some of the things listed on CaptainGeek, well after I kept emailing people the same links i had a thought, why not setup an amazon affiliate store. Basically, i’ve setup a small amazon site with a small selection of products (only those used for the tutorials on this site + related ones), purchases and payments are handled by amazon, however a small percentage of the sale goes to helping fund the server this website is hosted on AT NO EXTRA COST TO YOU :) so its a win win situation, please use the links whenever you can.

Our Amazon Store

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Ever wanted to be able to access the shared libraries from your home… when you are away from home? I do, since I started to use FreeNAS with Firefly iTunes/DAAP media server this is exactly what i want… I’m often away from home, and always wanting to access my media library from within iTunes…

Bonjour (mDNS) is what the iTunes / Firefly DAAP server uses to advertise a “beacon” of your iTunes shared library to your local subnet (LAN), however this is restricted (due to industry pressure (RIAA)) to local area only, and not wide area (the Internet) as it once was… However its still easy to circumvent and work around this issue so you can listen to your shared libraries on the go!

This tutorial is aimed at Mac users, but the concept is possible on every OS using the appropriate tools…

Tools needed:

Once you have all of these it becomes easy, this is the general process of how it works Continue reading →

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Recently i had a thought… Most of my machines are sitting redundant and have upto 4 drives in each… without unscrewing every single one of out of my rack… i want to utilise all of that space into one giant zpool using ZFS.

Imagine combining the drive space resources of 10 computers into 1 giant drive? see where i’m going with this now?

So my idea is to make the drives in each machine available to the “ZFS Master” (the solaris box running the ZFS pool) via iSCSI which is a sort of “offer your drives at a block level over ethernet” protocol… then add them all into a giant zpool… the advantages of this are:

  • Utilising all of my hardware
  • iSCSI can work over WAN so i could use boxes i have in other cities
  • Have each Lun “individual computer + drives” power up via WOL (wake on lan) initiated by the ZFS Master
  • Greater level of redundancy possible.
  • Backup “ZFS Master” possible
  • Everything connected via either Gigabit Ethernet or Fibre Channel.

So imagine.. a rack full of computers with hard drives in them… at the bottom is a more powerful computer running solaris which mounts the hdd’s of every single other computer and adds them into the zpool… then advertises this zpool over AFP / SMB to computers in my house…

Yet another way to make a α size tb system out of old free components that could possibly outperform a £20,000 solution! =) I’ll post all of the results of my testing after the break in a few days :)

P.S. This idea is without considering performance as that is something i can work out later :) & thanks bda for your advice

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