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May 29, 2007


Looks interesting - LINA.

With LINA, a single executable written and compiled for Linux can be run with native look and feel on Windows, Mac OS X, and UNIX operating systems.

Check the demo video - its a bit geeky but you get a feel for how it works.

[/tech/unix] | [permalink] | [2007.05.29-06:37.00]

May 26, 2007

Punk Zine Archive

Back before the interweb the best way to find out about new music was the 'zine' - heres a collection of issues from Maximumrocknroll, Suburban Voice, and Heartattack. Alas no Forced Exposure.

[/music] | [permalink] | [2007.05.26-03:43.00]

Amusing Video's

Brilliant workplace safety training video from Germany for Forklift drivers. Starts slow but the mayhem reaches quite a climax.

One for anyone that does technical support - The Book. Pretty sure I've linked this before . . .

[/humour] | [permalink] | [2007.05.26-03:39.00]

Agile Infrastructure

A buzzword has been creeping into software development over the last few years - Agile.

For software development its all pretty good - the client gets what they want faster as usable code released more frequently takes precendence over traditional the Waterfall style model.

There is a spleen-worthy catch (or two) however -

Enterprise Architecture

If you're putting in point solutions or you already have a well established framework within which to fit your Agile-goodness then you're all set. If you haven't got the Architechture nailed (and I don't mean diagrams with lines connecting things up implying it'll all automagically fall into place) then you're going to be winging it.

At an operational level you'll have a bunch of systems and technologies going in with some questions about how it all hangs together - this kind of bottom up thinking will inevitably lead to a requirement to review whats just gone on and how it could be improved (which your integration partner will gladly charge you for when it should have all been planned out before anything went into production).

Ideally your Software Architect, Infrastructure Architect and Integration Partner would all sit around a table and plan how it'll all fit together before a single server is purchased. Throughout the process you need to involve the business itself in the process so that you actually build and deliver something that they'll actually use.

At an architecture level they need to determine what technologies will be used, the application framework will deliver, how it will scale, how it will move from dev to uat to prod, how easily other apps can be added into the framework, what training and resources are required, will applications be delivered externally, how will they be authenticated, if you have a CRM can the information be fed back into collaborative workspaces for the client or will there be islands of client metadata, how will these applications be managed and supported, will physical or virtual servers be used, what security will be in place, how will backup, recovery and dr occur, will systems be clustered or load-balanced etc etc.

Once all the pretty diagrams are in place they need to get to the nitty-gritty of how it will work in operation - what hardware to buy, what software, what network infrastructure, how the dev/uat/prod environments interact etc etc

Infrastructure Architecture

I reckon Agile & Infrastructure are two things that just don't go together - you can't make infrastructure up on the fly if you want anything more than basic services to support point-solutions. Infrastructure needs to be planned and documented to support whatever you want to build on top of it - once its in place then Project Managers, Analysts and Developers can be as Agile as they like.

Probably the single biggest factor (IMHO) in enabling an agile infrastructure would have to be Virtualisation. No more worrying about when and where hardware is going to come from and who will pay for it with the ability to provision new boxes in about 15 minutes flat. If it looks like you're heading down the Agile route convince the powers that be to invest and believe in a virtualised infrastructure.

It all seems pretty obvious that this stuff needs to be thought about but as an operations person if you start asking these questions you run the risk of not being 'Agile' and being perceived as the negative aspect of the development plan ('we can't deliver because the Systems team won't give us servers' or 'they won't give our integrator access to extend the Active Directory schema'). Of course Project Managers should ensure the 'big picture' is part of their plan but you'll often find PM's have tunnel-vision - they just want to get their project out the door and into the clients hands - how their application fits into the grand plan is out of scope of their project (its someone elses problem).

So plan and implement your foundations (see The Great Pyramid of Agile) before the buzzword-compliant methodology comes into play or you might find yourself playing perpetual catchup and being forced into a position of recreating the mistakes of the past by forcing in quick fixes.

[/spleen] | [permalink] | [2007.05.26-01:28.00]

NetApp Volumes & LUN's

A good guide us to place LUN's into Volumes grouped by similar Snapshot or Snapmirror regimes (as this functionality occurs at the Volume level). I think the techy term for grouping LUN's in this way is a 'Consistancy Group' - anything you need to get Snap'd together should be kept in the same Volume.

Another thing I picked up was that when allocating space for LUN's be sure to allocate twice the space you need to allow for Snapshots. This space requirement supercedes the default 20% allocated at the Volume level. For LUN based Snapshots the agent software on the host itself (eg SnapDrive for Windows or SnapDrive for Exchange) manages the Snapshot - it interacts with the SAN to ensure this happens properly but the SAN itself has no knowledge of whats inside the LUN.

What this means is that if every block in the LUN changes you need at least as much space again for the Snapshot or you'll get a disk-space error. Its unlikely this would occur - a situation in which it might would be a drive defragment which touched every block.

[/tech/storage] | [permalink] | [2007.05.26-00:17.00]

May 17, 2007

'Toaster' Mailing List

If you're considering getting a SAN or already have one you should check out the Toasters mailing list. I've searched the interweb for equivalent lists for HDS and EMC but haven't found any equivalent (that isn't actually hosted by the vender itself).

Its completely independent of NetApp but is an excellent place to ask questions or search for answers in the list archives.

A good overview of the list is here.

[/tech/storage] | [permalink] | [2007.05.17-06:12.00]

South Park & Libertarians + More

One of the oddest mashups - The Invisible Gnomes and the Invisible Hand: South Park and Libertarian Philosophy.

Interesting tips - Why, oh WHY, do those #?@! nutheads use vi ?

Amusing - Science vs Norse Mythology.

Might be something useful here - Open Source Projects: 15 To Watch. Lots of multi-media tools + wireless/video-card management among other things. Nothing overly compelling though.

Scientific American - 15 Answers to Creationist Nonsense.

If you're a 2000AD fan then check out Dave Bishops auction of his own collection including Prog 1.

Looks useful - Incra ruler. Wonder if they have a metric version . . .

Amusing - Judge a Book by its Cover. Nascar themed romance novels ?

[/links] | [permalink] | [2007.05.17-06:05.00]

May 16, 2007

Solaris + iSCSI + NetApp

When you get down to the nitty gritty of configuring an iSCSI connection theres not actually a nice guide to getting this done. Sure there are plenty of docs and white-papers on the topic but many of them are either to detailed or not detailed enough (NetApp, Sun and Microsoft are all guilty of making something which should be simple more difficult than it needs to be).

From a Solaris perspective there are a couple of really good guides that fill in the blanks between the Solaris & NetApp documentation:

* OpenSolaris and iSCSI: NetApp Makes it Easy

* iSCSI Examples

[/tech/storage] | [permalink] | [2007.05.16-23:22.00]

NetApp Backup Idea

A cunning way to do your SAN backups:

Schedule a job to mount your LUN's to the backup server and backup a SnapShot to tape from there. Requires a bit of scripting and tweaking but it should provide much more flexibility than trying to backup each server individually.

That way you can avoid being reamed by backup software vendors on a per host basis. You may still opt to do an NTBackup to file for servers and applications but the databases will reside on the SAN and get backed up to tape.

[/tech/storage] | [permalink] | [2007.05.16-22:32.00]

Aggregates, Volumes and LUN's

I'm not a storage person so it took me awhile to get my head around the terminology. I suspect Sysadmins who host databases get harassed regularly by their DBA's about this stuff on a regular basis and as a result are much more intimately acquainted with this stuff than I am. One feature that helps the Sysadmin stay out of DBA initiated RAID-config-hell is that DataOnTap (the NetApp OS) only supports RAID 4 or RAID DP (similar to RAID 6) - note that the 'D' in DP is for 'Diagonal' not 'Dual'.

In NetApp land -

An Aggregate is a collection of disks - this is fairly straightforward. One thing to remember is that for every aggregate you lose a disk to parity data - fine if you have multiple shelves of disks or groups of disks of different capacity (eg you might aggregate 7 15k 72Gb disks and another aggregate of 7 10k 300Gb disks) but not really needed if you have only a single shelf with all disks the same. I guess there are plenty of reasons you might want different aggregates on a single shelf but if you're not doing anything fancy you may as well stick with one). Its easy enough to expand an aggregate by adding disks but its not easy to downsize an aggregate.

A Volume is a chunk of space within an aggregate - note that by default the DataOnTap OS is in vol0 within aggr0. Don't mess with vol0! If you're doing CIF's or NFS sharing (eg NAS type functionality) then you'd dish up your shares at a volume level. Volumes come in two type - the old style TradVolume and the newer FlexVolume - unless you have a special requirement you're better off with a FlexVolume which lets you resize it on the fly.

A LUN is a SCSI term (Logical Unit Number) to reference an individual disk. From an NetApp iSCSI point of view (probably Fibre-Channel too) a LUN is a big file that exists in a Volume. From a server perspective the LUN is visible as a raw disk device to make merry with. A LUN can be easily resized (up or down) but be aware that the NetApp has no inherent knowledge of whats inside a LUN - this has implications for SnapShots - if you need to Snap a LUN's contents you'll want to get SnapDrive and/or SnapManager (depending on the app using the LUN) which acts as an agent on the server (which does understand the LUN's contents) to initiate a Snap within the LUN from the NetApp.

In terms of layout we were initially tempted to create a Volume per application (eg Exchange, Oracle, SQL etc) with multiple LUN's inside each volume. We're now looking at a Volume per LUN as this will give us more flexibility in terms of Snapshots & SnapMirroring (or restore from Backup).

[/tech/storage] | [permalink] | [2007.05.16-22:00.00]

Teaming your NetApp Nic's

We bit the bullet and bought two NetApp 'toasters' - a FAS270 for our DR/UAT site and a FAS270c ('c' for clustered) for our Prod site.

For 2Tb of storage apiece they were actually pretty cheap - we'll SnapMirror between the two sites, we'll use the SnapManager tools for SQL, Oracle and Exchange and iSCSI as our transport medium (Fibre Channel is to expensive and complicated although we will use it between our backup server and tape drive).

So I'll be collecting some tips here as we put real apps on these systems.

You can team your Nic's in a couple of ways - either singletrunk or multitrunk mode. Single mode is purely for failover - one connection dies and the other will pick up the connection. Multi mode provides failover, link aggregation and load-balancing.

If you have more than two Nic's you can do this via the web interface, if you've only got two then you'll have to use the console (obviously you can't reconfigure a Nic if its already being used for something else; eg if you 'ifconfig e0 down' you'll lose your connectivity to configure the trunking).

To create a multi trunk virtual interface called multitrunk1 with e0 and e1 issue the following command on the console:

vif create multi multitrunk1 e0 e1

Then to configure it do the usual:

ifconfig multitrunk1 [ip address] netmask [netmask address]

And you can brink it up or down in the same way as any other interface.

One important point to note is that if you do this from the console be sure to update /etc/rc & /etc/host to reflect the vif or you'll lose the interface after a reboot. The web interface does write this info to these files but its worth double-checking that the updates have been made.

[/tech/storage] | [permalink] | [2007.05.16-21:41.00]

ESX 3 Network Reconfig

From here Changing the IP address of service console in ESX 3.x :

esxcfg-vswif -a vswif0 -p Service\ Console -i -n -b

And don't forget to set the correct gateway in /etc/sysconfig/network or the command to configure the virtual switch interface will hang.

ESX is very cool and they've made it pretty compelling in terms of a step up on the free Server (and older GSX) versions. It include user ACL, virtual switching, more efficient hypervisor (the RedHat 7.2 upon which ESX is based is stripped to the bare bones) and more granularity in terms of resource allocation. One of the things that isn't made very clear is that if you want to leverage some of the bells & whistles (eg High Availability, VMotion, Backup, centralised licensing) you'll need a SAN (or NAS in a pinch) and another box - ideally physical although it could be virtual (obviously you can't do HA or VMotion if your ESX instance hosting the management box dies though!).

[/tech/virtual] | [permalink] | [2007.05.16-21:14.00]

May 10, 2007

Mac Uptime

My MacBook has an uptime of 40 days and counting without a reboot . . .

Pretty good stability for a laptop (or computer of any kind).

My MacBook has been the fastest and most stable Mac I've ever owned. Highly recommended if you're in the market for a non Windows laptop.

[/tech/mac] | [permalink] | [2007.05.10-19:31.00]

May 09, 2007

Humourous Embroidery + More

Check the awesome embroidery on these womens shirts - Lochers Collection. Be sure to view the other designs and zoom to see the stitching. Certainly a twist on the average humourous t-shirt!

Funky - Plane shaped C code for a flight-sim. Details on making it are here.

Useful tips - Top 10 Things Sysadmins Forget To Do. The USB stick paranoia is an odd one - even a floppy disk will store hundreds of documents and can act as a virus vector.

Handy - 10 Simple Knots

Cardboard radio-enabled homeless shelter - Shellhouse.

Interesting figures - Load Testing Virtualisation Performance. A VMWare seminar I attended had many real world examples of people using ESX to host external and internal servers on the same hardware using the internal virtual switches - performance was adequate for their needs. Our new ESX server will be used for dev primarily but we're hoping to get another to host some prod systems.

Looks good - Metasploit. Automated penetration testing tool.

For Domino admins - Best Practise Guides for Lotus Notes. Ed Brill also points to a review of the new SameTime client - Not the same old SameTime.

Crazy - Hydration Allowed: There’s Posh For You. Schools without playgrounds ?

Brilliant - Cools Business Cards.

Watch SpamTrap shred junk email!

Angrifying - Yezidi woman stoned to death in "honour killing". I thought we were in the 21st century ?

[/links] | [permalink] | [2007.05.09-18:28.00]