I’ve been meaning to post this somewhere for a while now and this seems like as good a time and place as any…

Time: the slight offset between our PC clocks and the Phone Clocks seems to have caused some confusion as to what you can trust as the accurate time.

The short answer is – PC clocks. They’re accurate to the second (and usually even more than that.)

To explain this we need to look at why we need accurate time on our computers, how we have done this in the past and how we do it today.

Why?

When ever you’re using your machine on the domain you hold a Kerberos security token, there is a record of this on the domain controllers (all of them) which contains its expiry time. When the token expires, you re-authenticate. Time features heavily in this process and if your times are out of sync by more than a few minutes you can’t renew and so can’t get on the servers.

Because of this the network uses a time hierarchy to sync the clocks across the domain to an extremely high accuracy.

SO… As long as our domain controller’s clock is correct, the domain time will also be accurate.

How it was done

As I mentioned, clocks are synced using a domain hierarchy. We call this method NT5DS (catchy eh?)

Basically, a PC or server can sync it’s time securely (certificate authentication) with a domain controller and a domain controller can sync it’s time with the primary domain controller.

The primary domain controller then received it’s time from an accurate hardware source, this was usually a GPS clock connected with a serial cable, later (if you tweak the registry) it was a secure time server on the internet (which will have either it’s own GPS time device or sync from a server farm which has one.)

When computers are switched off they use hardware clocks and a small battery to keep the time running but this is inaccurate and is discarded once the OS starts.

If once you contact the domain controller your time is off, you PC clock will speed up or slow down until you are in sync. This usually only takes a minute or two unless your time is out by more than 5 minutes, in which case you clock will jump to accurate time.

Problems we faced and how they were overcome

(How it’s done now)

We had problems with this method when we virtualised the servers. VMs don’t have batteries so they loose the time completely when we turn them off, to deal with this problem they synchronise with the host server.

The trouble with that is; the host servers are member servers on the domain, so they sync with the domain controllers and hold their time with the hardware clock on restart.

So time sync looks like this:

PC<——DC<——>Host

This two way sync between with DCs and the hosts with no accurate source caused a slow drift in the PC clocks. Everyone could still log on to the domain as all PCs had the same inaccurate time.

To remedy this, we’ve made some registry changes on the host servers to break the NT5DS hierarchy and force them to visit a time server farm for accurate time sync.

This is done in:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\W32Time\Parameters

by changing the ‘Type’ key to “NTP” and adding “uk.pool.ntp.org” to the servers list. (We’ve got a few more in there for redundancy.)

So from start to finish;

The Host server boots and takes its inaccurate time (it’s considered inaccurate but is probably out by less than a second) from the hardware clock.

The OS starts and the time is discarded when we can sync with a secure time source, the much more accurate software clock takes over.

The virtual DC starts, we ‘fake’ a hardware clock and push in the host’s time, once the OS starts we push the host’s time again but this time with the software integration services rather than a fake hardware clock. The DC will occasionally check this service for accuracy.

This accurate time is pushed to client PCs and member servers using the NT5DS hierarchy.

You visit http://www.greenwichmeantime.com/ and find your computer clock exactly matches (well, your browser only check as the page is loading… so if it’s out by 1/2 a second your PC clock is the more accurate of the two.)

…and the phone system?

The phone system doesn’t sync with an external time source and doesn’t have an accurate hardware time device. We have to manually set the time and it’s held in an inaccurate battery powered hardware clock on restart.

This causes the time to drift. I estimate by around 10 minutes a year (the phone system clock is fast, just in case you were interested in the drift direction.)

I think this is addressed in the next version of the phone system software.

So next time you need an accurate time reading, look to the task bar and not your phone.

But sometimes I do post and it has to be pretty significant subject to get me in the mood to write.

Today it’s something that has annoyed me: The E.On home energy monitor.

I received this device around three months ago and started using it right away. All was fine. My instantaneous energy use is shown on the screen, which is well set out, along with a little bit of historical data. I thought this device was great!

That was until last night, when I decided to plug it into my laptop in order to get the full stats that have been collected.

What a disappointment.

I disliked the software immediately as it came on a CD. In my mind, a USB device which requires CD software to be install has already failed the usability test. If it’s got a USB interface and requires software it should be installed or run from some flash memory on the device. I don’t think an argument can exist to the contrary of this statement.

The biggest shock was just around the corner.

The autorun software from the CD began to install the “eon database files”, this was actually and instance of MS SQL server express 2005!!! A device that requires it’s own SQL instance to be installed to get its data! That is absolutely appalling! So my home laptop is now constantly running a database server, which will always be impacting on the performance of the machine even when I’m not using the device. (Until I remove it tonight!)

Imagine if every device I used on my laptop needed a database instance, it would have a dozen instances running and would perform about as well as a lethargic slug!

How did this manage to be developed by such a large company without someone at some point saying…. “Hang on, databases run on servers or dedicated devices. This seems like overkill, maybe we should use something like XML.” Was there no design or testing done at all!!?

The final insult: the reports were rubbish.

I was truly disappointed with the experience of using the energy meter in this way. Mainly because I’d loved it up until now and wanted to continue doing so. It feels like they’ve only just missed the target on this and that’s why it’s so bad, if the design of the reports had been just a little better and the coding a little less sloppy this would have been an awesome piece of kit.

Ideally (Although this is probably/almost certainly not financially viable as a freebie) I’d like to see the device with a wireless network adapter and running a simple web server.  That way I could log onto it any time from any PC in my house and with a bit of jiggery pokery on my router could even keep an eye on my energy usage from the office.

I’d love to hear from anyone who disagrees with my opinion on this (and it is of course only my opinion and I’m cool if people do disagree.) Especially if you were involved in the software development for this device, who knows, maybe you’ll turn my thinking around.

I discovered how easy it was to create ringtones for my iPhone the other day, up until then I thought the only way to do it was to buy them or jailbreak. It’s pretty easy and doesn’t require any third party software.

Here’s How;

1. Open up iTunes and select your track

2. Right click the track and select “get info”

3. Your ringtone will need to be 30 seconds long so click the options tab and use the ‘Start time’ and ‘Stop time’ to select your 30 second snip, then click OK.

4. Right click the track and click ‘Create AAC Version’ – This will create a new file with extension *.m4a leaving your original intact. (so you can remove the start and stop times and sill listen to it)

5. Check the length of the new file to make sure it’s 30 seconds or less.

6. Right click the file and select ‘Show in windows explorer’, once the window opens go back to iTunes.

7. Right click the new file and remove it from iTune but don’t send the file to the recycle bin.

8. Go back to Windows Explorer and change the file extension from ‘*.m4a’ to ‘*.m4r’.
- You might need to goto tools, folder options, view and uncheck ‘hide extensions for known file types’ to be able to do this.

9. Drag your ringtone file into iTunes.

10. Sync your phone and use settings to select and test your new ringtone.

I hope you find this useful.

Bye,
Jon

Then the problems started, I tried to virtualise our exchange server which happens to be use SCSI hard drives, now I’m not sure why it happens but when the P2V process gets to “Install VM Components” after the reboot I’d just get Blue screens with error 0x0000007b.

Turns out this was due to a certain registry entry being incorrect, unfortunately I couldn’t get the machine to boot to change the reg setting!

The solution was this, (I’m taking you from start to end here guys);

1. Run through the P2V wizard on SCVMM, set things how you like them but don’t complete the wizard.

2. When you get there click “view script”, save this as a .ps1 file

3. Cancel the wizard

4. Open the .ps1 file in notepad and add “-SkipInstallVirtualizationGuestServices” (without speech marks) to the end of the last line that starts with New-p2v (probably the bottom line)

5. Save your file

6. Open up SCVMM powershell and run your saved script

7.Wait for your machine to virtualise

8. log off your SCVMM and log on to your host machine

9. open up Hyper-V manager

10. Connect to your fresh VM and log in (you’ll have to do this without a mouse, this will be fixed later)

11. At the top of the window, click action and then click “insert integration services setup disk”

12. run through the setup (DO NOT REBOOT! or you’ll be back at the blue screen and have to start again)

13. Open up  the registry and navigate to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Wdf01000

13. modify “Group” so that instead of “Base” it says “WdfLoadGroup“

14.  Eject the virtual disk

15.  Reboot 

DONE! you should now have the mouse working and be able to manage your VM from SCVMM just like any other VM. Thanks to Jason Gauthier for posting this on TechNet.

In other news, I’ve started using twitter so follow me! my account is jonathonmoore.

Laters,

Jon

Now, these are all great things, don’t get me wrong on that, reducing the number of servers needed from 50 to 10 might be reason enough for a large corporation to virtualise, I’m sure the electricity bill saves would be pretty amazing, but what I find really exciting is the resilience it can bring to your organisation. Imagine this, you have six virtual servers running on three physical boxes, it’s the middle of the day, everyone is working hard (or hardly working) and the motherboard fails on the box running exchange and another LOB server, instantly the entire company looses access to emails – MAJOR PANIC ENSUES.

But it’s fine – you log onto virtual machine manager and move the virtual servers to one of the other physical boxes, 10 minutes later everyone is working again and you can have another latte and feel good about how much of an awesome IT Manager/sys admin/tech support guy you are.

To me this sounds like a very good thing, which is why over the next few weeks I’m going to virtualise as many of our servers as I can. Currently I’ve identified seven servers that are prime for the switch, these include two domain controllers, an exchange server, a SQL server, an ISA server (running as an edge firewall… more on this later) and a couple of LOB servers. three of these servers run on pretty powerful boxes so I’m planning to simply beef up their memory and use those as my physical hosts.

My data storage will be taken care of by a Broadberry Cyberstore 316S DSS SAN, this will hold all of the virtual hard drives, I’ve identified this a possible single point of failure, so I’m going to put new, large, hard drives in the physical servers so that if the SAN ever fails I can restore the virtual drives from backups, right onto the physical servers.

For anyone looking to do something similar, I’m going to post up what I go through to get this working… job number one, buy the hardware and the licenses! This will be done on Monday, I’ll let you know how it all goes and give you a progress update on what I’m doing.

I’d love to hear from anyone else doing similar projects like this or anything else I’ve ever talked about on here (love, life, servers, etc) so get in touch!

Laters

Jon

I’ve gone for the 16GB as I just don’t think I’ll ever have the need for a phone with 32GB of data storage (I understand that this may be quite similar to a Bill Gates quote from the 80′s – “640K should be enough for anyone!” so I’ll add..) at least for the next 18 months, which is my contract length.

I bought it on the first day of release and so far I love it, I’m a true apple convert. I still regard myself as a ‘PC’ to quote the adverts, but apple’s are pretty… which for home and personal use is fine – but for business you just can’t beat MS W2k8 and Exchange 2007 (apple fan boys – don’t even bother complaining about my opinion, just accept that it is my opinion and you can have your own)

As a side note, Sarah and I have now been together for a whole year! woo! Our relationship is great and we’ve now looking for an apartment together.

Anyways, check out this brief fairly long youtube clip of the iPhone 3GS… then buy one… sorry it’s a bit corny.

Laters,

Jon

There is one major reason for the latest server move - SUPPORT! My last host was rubbish at it, now I’m not going to name and shame here… (UKHOST4U – DON’T USE THEM!) but I will tell you about the situation which lead me to this conclusion. It all started with a DNS problem in the office. I arrived at work last Wednesday to find that the entire company was no longer able to recieve emails, to cut a long story short, our ISP had messed up and deleted our DNS records, during this period of down-ness I used my personal email address to send a number of test emails to my office address, they came through eventually, once the DNS records had been recreated.

The problem was, all of my personal emails had been marked as SPAM by our content filter, I allowed them through so that they would be delivered but then exchange and outlook also categorized them as SPAM. Now I saw that as a big problem, if two separate applications were marking my email out to be SPAM I’d wager that many of my emails may be blocked by other people who I was sending to. When I typed the IP address of my mail server  into a browser, the content filter struck again and informed me that the IP address was blacklisted as… ahem, an adult category.

I was blown away, someone who was sharing my IP address must be hosting something pretty nasty which had resulted in everyone on that server being tarred with the same brush. “Oh well, no problem” I thought, as I sent off my findings to the tech support forum of my host, expecting the IP address to be changed or for my content to be moved to another server with minimal fuss.

Ohhhh nooo, after many emails back and forth with my host taking no action to resolve the issue, the final straw came. An email from my host informed me that as SPAM filtering was opt-out I could work around the issue by contacting people who I wanted to email to ensure they switched off their SPAM filter first!!!

Now, I don’t know about anyone else, but I see phoning everyone in the world that I might ever email and asking them to turn off their SPAM filter seems like a pretty pathetic response. I was even more annoyed when they wanted £10 + VAT per domain to transfer away from them, well there was no way I was paying that, they have had all the money they’re ever getting from me! So I went to nominet and for £11.50 was able to transfer all of my domains in one go to my lovely new host EUKHOST check out www.eukhost.com for a good hosting deal, I’ve gone for the gold package, I’ve also paid for a dedicated IP address to ensure there is never a repeat of this problem.

I took this opportunity for a bit of a redesign and so here it is, my new look website. I’ll probably tweak it a little over the coming weeks, I’m going to try and add a few more pages too – about me, contact form, gallery, etc. Anyway, drop me a comment and tell me what you think!

Jon

Over the next few weeks or so I’ll post some screen shots and instructions on what Ive done so far and keep you up to date with what I’m doing and how I’m getting on.

I’m excited about all of the functionality that OCS will bring to our offices, so far I’ve got the enhanced presence working so the clients report us as being ‘on a call’ when ever we answer of desk phone and we’re able to dial with the client software too. I’m having a little trouble with ending calls, the software has a tendency to miss the end of the call – that is, I hang up manually by putting down the receiver and my computer keeps my status as ‘in a call’ and continues to count up the call time.

That’s a bit of a snag and I’ll get it sorted out later, the thing that I really want to get working next is the Microsoft exchange integration. Ever since I went to the Microsoft EVO roadshow with my friend Will when we were both working for PriceMaurice, I’ve wanted to have my emails read to me by the exchange server when I call it from my mobile.

Unfortunately it seems that to enable a user for Unified communications you need an enterprise exchange CAL, so I’m going to have to see if I can get hold of a few of those for development purposes.

To recap;

I’ve got enhanced presence working along with click to dial, next I want voice email and voicemail working and call forwarding to work.

In other news, my last post had a clip from Les Miserables, which at the time may have seemed quite random. Well the reason for this was my last trip to London, Sarah and I dropped in for a night just to grab some dinner and see a show or two; this time it was Wicked on the Friday night (what else!) followed by the matinee of Les Mis the next day. The Mis was amaaazing. We bought £20 each tickets from the box office about an hour before the show, then went to the Costa across the road whilst we were waiting.

Our seats were really, very good. They were classed as “slightly restriced” just due to the fact that they were so close to the stage, but really I don’t think they could have been better, the actors were sooo close, sometimes it was quite scary when they were shouting.

Wicked was great as expected, although I was slightly disappointed that Kerry Elis wasn’t playing the lead of Elphaba, the understudy was brilliant though which made it matter less.

I’ll get the pictures from the weekend up in the gallery once I’ve got it fixed… which brings me onto my next subject – the website redesign, those of you who frequent these pages may have noticed a slight change, I’d had my old layout for about 3 years and really wanted something a bit different so I’m trying this out for now. I’m not totally convinced this is how it’s going to stay but I like it so far. Anyways, that’s your lot for now – if you haven’t already then check out the video from my last post.

See you soon,

Jon

Well… A short one, but one at least.

I’m going to be re-writing much of the content of the site over the next few weeks as most of it is now out of date. 

For now I’ll leave you with a picture of my new car (called zeeta) and a video from youtube.com

Zeeta the zetec

 This is ”At the end of the day” and “One day more” from Les Miserables. Make sure you watch it all, the second song is by far the best of the two.

Anyways, this is just a intermission post really.

More content coming soon!

Jon

The first of these major changes is of course “the new job”, yes, that’s right. As of 5th February 2009 I will no longer be employed by PriceMaurice Limited. After a brief and frankly unexpected conversation with Si, a friend of mine from uni, I was told I should email a copy of my CV to J.H. Austin who were looking for a new “Systems Development Manager”, a couple of emails and about half and hour later and a job interview was arranged. Out came the suit and off I went for the meeting, upon arrival I was met by two nice chaps who would be conducting my initial grilling, Alan and Glenn both seemed very friendly and made me feel quite at ease, which I’m sure helped with the interview. Later I would meet Jonathan, the M.D, we only talked for a short while but I found him to be very interesting and look forward to meeing him again.

J.H. Austin sounds like a very interesting place to work and it looks like they’ve got a good couple of exciting projects lined up for me. I’ll be sorry to leave my place at PriceMaurice as it’s such a nice place to work and I’ll be forever grateful to Matt, the MD, for giving me my first real I.T position and the opportunity to gain all of the experience that’s helped me so much. That all being said I’m also really excited to get into a larger network environment and really get my teeth into something a bit more complex than the type of work that is available at PM.

I’m as of yet unsure of whether I’ll be starting to fix peoples computers in my spare time as I did before I worked for PriceMaurice, but I think it’s a distinct possibility. That little bit of extra money is always nice, so bare me in mind.

I’ve also bought a car! woo! Bertha the MK4 1.6 litre 8 valve red VW Golf has been a lot of fun over the last couple of years, but with a new job and an ever increasing maintenance bill I’ve decided to splash out a bit and go for something a bit newer, and here it is;

New ford focus

A new shape 2008 Ford focus Zetec oooooh (but mine is black)

I’m hoping to keep this new car for at least the next four years – mainly that’s because that’s how long I’m going to be paying for it, but hopefully those years will pass mostly mechanic free and it’ll be a great car. If I’m lucky it’ll be as good a car as Bertha has been.

The final change, well, this one is more of a decision to change, is that this year I am determined to move out (as I have previously mentioned) but I’ll keep you posted on that one.

In all, 2009 couldn’t be looking better. I’ve been with Sarah for over 6 months now and couldn’t fell better about it, I feel so lucky that our chance encounter occurred when I think about how easy it would have been for it not to have happened. I really do love her and I honestly don’t think I’ve ever felt like this about anyone before… yes, yes, cliche I know but I find myself trying to spend as much time as I can with her, which isn’t really something I’ve done for anyone else before.

So as Lilly Allen put it; “That’s what makes my life so sexy-fantastic” …well in the radio edit anyway.

Jon