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…
Recently I began experimenting with KVM virtualisation in the Linux Kernel. Its a great technology that if your CPU supports VT-x / AMDV offers almost (really, almost) bare metal level performance inside Virtual Machines. It works on most Linux flavours and has a couple of handy management tools such as virsh and virt-manager. However, one thing I thought was always lacking and annoying me was of course, the ability to manage my Hypervisor from my iPhone / iPad when on the move! Time for an experiment I thought; then out came “KVM Remote”
KVM Remote on the iPad and 3 Different Remote Hypervisors
Its universal so works on both the iPhone and iPad and is extremely bleeding edge right now, but works! and is incidentally the first App i’ve made that doesn’t have selfish fiscal intentions, so theres another great reason to download it from the AppStore now!
P.S. i’ll be updating it regularly adding more features as requests come in.
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 →
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.
It’s a bit of a random thing you’d think, but recently I had an issue where one of my servers would keep dieing when under abnormal load… So I thought, how can i replicate this in a lab environment… So I wrote a tiny bash script (that you can just paste into a terminal) that will max out each “thread” of the CPU until you kill the processes or reboot… Useful for stress-testing or burning in a CPU…
I’ve been playing around with some IDN’s and TLD’s and DNS etc…. i’ve realised you can create IDN (punycode) subdomains to any existing domain, in addition, i’ve created my own TLD, and setup a DNS server that works for this purpose. If anyone would like an IDN or a custom TLD, get in touch!
Following on from my previous post regarding AFP and iSCSI benchmarks i’ve decided (after many requests) to post a few raw benchmarks of the system gathered by bonnie++, the environment is as follows:
CPU: Athlon 64 3700+ RAM: 2gb DDR400 Controllers: 2x SATA-II and 1x SATA-I Hard Drives: 7x Samsung 2tb Spinpoint F3 5600 RPM OS: NexentaStor 3 ZFS Config: Standard raidz1 with dedup=off and compression=off
So I gathered a few results… after some annoying results I found a bottleneck in my system on 1 of the drives that seemed to bring the benchmark result down greatly, however once this was worked out I acheived the following: Continue reading →
I’ve been very busy lately, here is one of my latest incarnations, a Virtualisation Linux Distribution, which you can use as a live-cd or a bare-metal installer, it is debian based with virtualbox. Everything configured out of the box. You can run Linux/BSD/Solaris/Windows/Other virtual machines on this distribution, even if your system does not support virtualisation natively! =) Please note, this release is super early, it works, but very bare. In the coming weeks i’ll make it a pretty fully functional system. Continue reading →
Have you seen the Drobo box? it’s a SAN that allows you to create giant volumes and hot swap out hard drives at will with failure tolerance… bad news, is that it costs close to £1000 even without the drives, i’ll explain how to make a better one… for free! =).
ZFS (Zettabyte Filing System) is Sun’s newest file-system offering, its supported on FreeBSD / Solaris natively and Mac OS X / Linux / Windows via third-party utilities. I’m gonna keep this guide, simple, short and sweet, so i’ll bullet list the main features that wow people about ZFS =)
It can store up to 340 quadrillion zettabytes of data (no other production filing system can do this)
It checksum’s your data on the fly so you can check for integrity by “scrubbing” it (identifying broken drives before they completely die)
It supports every raid configuration you can think of natively and doesn’t suffer from the raid5 data-hole.
You can create snapshots of your data that do not waste hdd capacity.
Volumes or “Pools” can be expanded at any time, so you can start with a 2tb raid, and increase it to a 10tb raid with no data loss.
You can mix/match capacities, brands, rpm’s of drives.
Its reliable* (on officially supported incarnations anyway)
Its a memory whore (don’t try it unless you have 2gb ram on your system)
Its supported in the latest version of FreeNAS (0.7)
Allows hotplugging of drives when one fails (so you don’t lose data/time)
Hotspares are supported
Can be easily transferred / transported to any other ZFS supported system without extensive configuration or any data loss.
Its free free free free (under CDDL).
Think of a hardware raid5 or a geom_concat/raid and then think about those again, but without any of the issues / flaws they have… thats what ZFS is! =)
So lets get started, I’ll run through creating and bringing a ZFS raid online first, and then some maintenance commands afterwards. I suggest trying this on a Continue reading →
If you want all of your storage in one centralised place, that is accessible using just about any protocol out there, then you’ll need Network Accessible Storage (NAS), This can be often very expensive, upwards of £1,000, however you should firstly try FreeNAS, its a project based upon FreeBSD which provides a very comprehensive NAS environment supporting all common protocols including iSCSI, so you can even set Vmware to boot from hard disks stored on your FreeNAS! The whole thing is a bare-metal installer, and runs on any hardware manufactured within the past 10 years or so! Although for iSCSI you’ll need a minimum of 256mb Memory. So try it out, tell me what you think. Personally… I LOVE IT!, I’ll be posting a tutorial on getting VMware to use an iSCSI target defined with FreeNAS Later! Until then grab FreeNAS here P.S. it supports IPV6 =)