System Center solutions help you manage your physical and virtual IT environments across datacenters, desktops, and devices. Using these integrated and automated management solutions, you can be a more productive service provider for your business. As a result of feedback we have gathered from all around the IT Pro universe, some great changes have been made to the System Center Evaluation experience.

With the release of the System Center 2012 beta evaluation in the TechNet Evaluation Center, you can now download and evaluate the most current versions of System Center 2012 products with a single registration.  This includes all of the following pre-release products:

• System Center Virtual Machine Manager RC
• System Center Configuration Manager Beta
• System Center Operations Manager Beta
• System Center Orchestrator Beta
• System Center Data Protection Manager Beta

However, if you aren’t ready to evaluate all the System Center products you can select the specific products you want to evaluate, again with only one simple registration as opposed to the multiple registrations previously required.

Head over to the System Center 2012 Evaluation Center and check it out

Source: http://blogs.technet.com/b/uktechnet/archive/2011/10/25/download-microsoft-system-center-2012-pre-release-products.aspx

Recently, I had a request from a customer, where he wanted to encrypt his web.config file ( wee, a part of it ). Since he didnt know how to do it by himself, he asked us to do it.

Basically, the procedure is very simple.

First, open IIS manager and find the web site you want to encrypt. Got it? Great, when you’re there, look at the site ID, write it somewhere.

Then, run command prompt ( as administrator ) and position yourself in the :

C:\Windows\Framework\v4.0.30319\

In case your application is running in .NET 2, position yourself in the V2.0.xxxx folder.

Type in the following command:

aspnet_regiis -pe “connectionStrings” ” -site “IDnumber”

What will this command do?

It will encrypt the connection string part of the web.config file, so it cannot be read in some text editor; ofcourse, your web server will still be able to read the connection string from the file, dont worry

BUT WHAT IF I HAVE A VIRTUAL DIRECTOY, AND I WANT TO ENCRYPT THAT web.config FILE?

No problem at all, just use this command:

aspnet_regiis -pe “connectionStrings” -app “/YOURVIRTUALFOLDER” -site “IDnumber”

Notice that I added a “-app “/YOURVIRTUALFOLDER” part to the command.

Thats all for today Stay smart and bright! Bye bye!

Not very often, you will get the following error:

Error:
The server principal “” is not able to access the database “” under the current security context.

This is because the MS SQL Server is attempting to execute a SQL query to retrieve a list of databases along with  some other formation about those databases. Some of  that information is “Collation”, which, ofcourse you don’t have permission to view for all databases, since  you’re in a shared hosting environment and you can only have access to your database..

Solution is pretty straight forward :
1. In Object Explorer, click on Databases
2. Display Object Explorer Details (F7) or View > Object Explorer Details
3. Right click the column headers and de-select “Collation”

4. Refresh Databases or reconnect to ste machine.

Thats it

Bye bye 

Few days ago, I had a strange issue where all of a sudden, the statistics on some of my web servers stopped working.

First thought was, nah, its some PEBKAC issue. Statistics was working great, and nothing in the configuration wasnt changed for months. The customer must have some outdated link, wrong password or something else.

The error my customers were getting is :

Microsoft.Web.Services3.ResponseProcessingException: WSE910: An error happened
during the processing of a response message, and you can find the error in the
inner exception. You can also find the response message in the Response
property. ---> Microsoft.Web.Services3.Security.SecurityFault: An error was
discovered processing the header ---> System.Exception: WSE065: Creation time of
the timestamp is in the future. This typically indicates lack of synchronization
between sender and receiver clocks. Make sure the clocks are synchronized or use
the timeToleranceInSeconds element in the microsoft.web.services3 configuration
section to adjust tolerance for lack of clock synchronization. --- End of inner

The part of the error that gave me a hint is:

Creation time of the timestamp is in the future. This typically indicates lack of synchronization between sender and receiver clocks.

Soooo…I login to my WebSitePanel server and check the time…it was 9:24 AM. I login to the web server that is giving the above mentioned error , also 9.24 AM.

First reaction…WTH!!?!?!?!?

I thought to myself: “Nah..I’ll try it anyway. Left click on the Clock, change time and date settings, Internet time, Change settings, and then click the “Update now”. All of a sudden, my statistics started to work. GREAT, that part is solved.

Now, lets try to find the reason for this behaviour, ofcourse, there are hundreds of articles on the web, and every single one of them is pretty much useless in my case .

My search was pointless, and quoting James May from Top Gear, I thought to myself:

“Oh cock!”

Well, atleast let me try to patch the thing up. My idea was to use our own ntp servers on all our windows machines ( instead of time.windows.com, or some other ntp server listed ). In order to achieve this, you must replicate these steps:

1. Stop the W32Time service with : C:\>net stop w32time
2. Configure the external NTP server by  typing : C:\> w32tm /config /syncfromflags:manual /manualpeerlist:”1stNTP.domain.com, 2ndNTPserver.domain.com”
3. Then make your  PDC a reliable NTP server with  C:\>w32tm /config /reliable:yes
4. Start the w32time service with : C:\>net start w32time
5. You can check the NTP servers configuration by typing: C:\>w32tm /query /configuration

Next thing I decided to do was to autmate the time sync, since I didnt want to rely on Windows to do it.

Command for that is pretty simple : c:\w32tm /resync

In order to achieve that, I created a batch file with the above mentioned command, set it to run every day at 12:00 AM, and thats it. Never heard of time sync issues EVER again!

Bye, Alesandro

Couple of days ago I installed SCVMM  in order to test it out, since we are developing our IAAS solution. Everything seemed great until I found out that SVCMM doesnt have any API which can be used to create/turn on/off  new machines.  Yes, I know everything can be scripted thru Powershell, but it sucks that we need to create separate applicatons that will give us that feature. Imagine a solution where PRTG, Nagios or any other tools monitors your server… sees that the CPU load went up ( or any other condition) and starts up a new virtual machine  using API?

Its funny how the guys at MS fails to see the basic requirements for a modern cloud solution; do I have to mention that after years of HyperV being RTM-ed, we still dont have an option to limit a machines uplink speed!? Come on guys…SERIOUSLY!?!?

I know that you already have this  little piece of software created, release it…pretty please!? I know that Microsoft sees HyperV in some giant corporation where they dont have a need to limit the uplink of a virtual machine, but IMHO, hosters are having a bigger “market” share  than big corporations, think about us, pretty please with sugar on top .

Oh, what about promiscous mode for network cards? You  have no idea how much would I like to use SNORT on my HyperV virtual switch, but…I cant

What about the limit on only 4 cores per virtual machine? This is a VERY limiting factor. I’m in a situation where i have a 2x six core, 48 GB ram server which I want to turn into ONE virtual machine ( live migrations, scaling, etc…), but I cant…I can only turn it into a 4 core, 44 GB machine, effectively, wasting other 8 cores!?

I would really love to get in touch with someone from Microsoft Virtualization team and send them a list of must-have changes Someone knows some insiders?

Let me make one thing clear, I love Microsoft, but lets face it, there is lots of work that needs to be done. Admit it or not, the guys at the “Linux Camp” have much more options and features regarding virtualization. I really, really love HyperV, but some limitations are just plain unlogical/stupid.

Sorry for a bitter post, but I had to throw out my frustrations

Couple days ago, I had to setup a machine for a customer of ours who will host a web site for some Microsoft conference in Croatia. Since, this is the biggest IT conference in Croatia, I really tried to take everything to the next level and tweak the hell out of that machine

For stress testing, I used Siege with  url.txt file where I saved about 20 links from the web site I was testing, in order to emulate the real world scenario as much as possible.

So, for starters, lets throw out some numbers, to see how the machines copes when the IIS install is out of the box :


The test has been run with 150 concurrent users.
Lifting the server siege...      done.                                         Transactions:                    5215 hits
Availability:                 100.00 %
Elapsed time:                  59.83 secs
Data transferred:             472.64 MB
Response time:                  1.69 secs
Transaction rate:              87.16 trans/sec
Throughput:                     7.90 MB/sec
Concurrency:                  147.32
Successful transactions:        5215
Failed transactions:               0
Longest transaction:            5.99
Shortest transaction:           0.25


So, lets take look on the Longest and Shortest transaction value – pretty jumpy, right?

It took the machine to serve the page, in a range of 0.25 to almost 6 seconds? SLOW!

STOP!  Tweaking time

One note – do not run 32 bit apps in 64 application pool – waste of resources!

Since this is a website which has around 120 requests to the IIS server for loading one page  I have TURNED OFF the compression!

Why? Simple tradeoff, more bandwidht for less CPU usage. With compression turned on, site had around 1.2 MB ( a lot, I know ), but with compression turned off, site loading time went down for almost 50%, and the site size went for for only 100 KB   -  a good trade off in my opinion!

Next -  lets cache this sucker out, I turned on caching for both dynamic and static content, pretty simple setting for a huge improvement!

Now, lets dive into some more complex tweaking -  .Net and registry tweak.

Does the “word”  MaxConcurrentThreadsPerCPU sound familiar?

Basically, with standard out-of-the-box setting, number of requests per CPU is limited to 12.

By default, this entry doesnt exist in the registry, so we need to add it.

MaxConcurrentRequestsPerCPU within HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ASP.NET\2.0.50727.0 determines the number of concurrent requests per CPU.

Since that value in .NET 4 is already set to 5000, there’s no need to change that is you run a .NET 4 application, but in my case, I had applications with .NET 2, .NET 3.5 and .NET 4 running on the machine, so I have set the value  MaxConcurrentRequestsPerCPU to 0 – which means unlimited.

Lets do some load stress with the new IIS and .NET setting. Again, we will run Siege with 150 concurrent users.
Lifting the server siege...      done.                                         Transactions:                    8171 hits
Availability:                 100.00 %
Elapsed time:                  59.58 secs
Data transferred:             643,80 MB
Response time:                  0.96 secs
Transaction rate:             137.14 trans/sec
Throughput:                     10.73 MB/sec
Concurrency:                  131.67
Successful transactions:        8171
Failed transactions:               0
Longest transaction:            1.99
Shortest transaction:           0.15


So, as we can see, we had almost 3000 more transactions, better transaction rate and load time improved over 3 times ( 0.15 to 1.99 sec ).

But wait, there’s more, in the next post, we will do some network level tweaking, and see if we can get even more juice from the machine.

NOTE:  Since I didnt write the applications  and didnt have access to them to review them, I had to optimize the server as much as possible.

So…today I had a very interesting issue. All of a sudden Nagios went red with the message: CRITICAL : – total: 232.82 Gb – used: 212.67 Gb (91%) – free 20.15 Gb (9%) on one of our SQL server. I was like..”NO! It cannot be. I clearly remember that this machine had over 150 Gb of free space yesterday!”

I log in to the machine, and automatically go to the data folder of SQL server thinking that some customer has a HUGE! log file on his database; so, right click – Select All -> Properties… only 50 Gbs of data…hmm…not here!

At that moment I notice that the server isnt “jumpy” as usual, so I start Performance monitor and see that the Avg. Disk Queue is off the chart!  That definatelly isnt right…

Since that machine is using Windows 2003, theres no too good way to see what application is using so much disk I/O ( beside FileMon ) , I start the FileMon and se that the SQL service is writing HUGE amount of data to its ERRORLOG file.

By navigating to the folder, I see that the ERRORLOG file is over 120 Gb big so opening it in Notepad, Context or some other file was out of the question, since it would kill the machine completely.

So, lets turn to powershell once more. In order to be sure to not kill the machine, since its in production , I have moved the file to an empty machine to opened it there.

Powershell : cat errorlog +ENTER after that powershell started to list the entire content of the file, and it took about 15 mins until it reached the end. AMAZING

By examining the log, I notice ( it was hard to NOT notice it ) litterally millions of these entries:

Could not allocate space for object ‘dbo.tblComments’.'tblComments’ in database ‘DATABASEname’ because the ‘PRIMARY’ filegroup is full. Create disk space by deleting unneeded files, dropping objects in the filegroup, adding additional files to the filegroup, or setting autogrowth on for existing files in the filegroup.

What happened here?

The site that was using that database is poorly written and was allowing everyone to post comments on the articles without any security check, so it soon reached the size limit set on the database.  By further digging on the issue, I saw that the bots are posting about 4-5 comments each second which comes to about 18000 comments/hour…multiply that by 15-16 hours it took to fill the error log to that size, we roughly come to 280000 comments…that’s A LOT of comments!

After disabling the site and sending the email to the customer, situation on the machine looks like this :

The big drop on the green line is the moment where I disabled the problematic web site.

Fact number one: If you have a streaming server, you must install this extension!

Great, now that we’ve got this fact covered, we can move on.

IIS site says:

Bit Rate Throttling, an IIS Media Services extension, saves money on network costs by metering the download speed of media and data files. For media, Bit Rate Throttling accomplishes this by automatically detecting the encoded bit rates of 11 common media formats, such as Windows Media Video (WMV), Flash Video (FLV), and MPEG 4 (MP4), and then throttling the response to the client. For any other file or MIME type, Bit Rate Throttling allows administrators to configure custom throttling rules.

Now, lets explain the same thing in a bit simpler way.

If you have a server which streams any kind of media files, Im sure you have noticed extremely high bandwidht usage on that machine. In my experience, over 40% of the bandwidth is wasted! WAIT! WHY, HOW?

Answer is simple!

Scenario 1 ( server without Bit Rate Throttling extension ):

Lets say that you have a 100 Mbit link on your machine. A visitor with a 20 Mbit link will come to your site and click “play” on the newest promo movie you have uploaded.  What will happen, the server will send the ENTIRE video to the visitor in couple of seconds ( buffering ) and on the half of the movie, the visitor will see that he doesnt like your movie and go away.

What happened here? Half of the downloaded movie is wasted. The visitor downloaded the entire movie, but only looked at half of it. Efectively, you’ve wasted 50% of that movies bandwidth ( in a 100 Mb file, thats 50 Mb of bandwidth wasted )

This is where Bit Rate Throttling jumps in and saves the day!

Scenario2 ( Server with Bit Rate Throttling Extension installed ) :

Lets say that you have a 100 Mbit link on your machine. A visitor with a 20 Mbit link will come to your site and click “play” on the newest promo movie you have uploaded.  What will happen, the server will see that the movie is encoded at 700 kbps ( example ) and reduce the speed its sending you the movie ( buffering )  to 800 kbps or 850 kbps ( depening on what setting you choose ) so that you still have a smooth playback and some buffer in reserve ).   In this case, amount of bandwidht that could potentially be wasted is a lot smaller than the amount of bandwidth that would be wasted without this extension.

As I said before, improvements in bandwidth costs can be improved up to 40%! Thats not a small amount!

Features of Bit Rate Throttling:

• Seamless integration into IIS 7.x Manager
• Out-of-the box compatibility for the following media types: .asf, .avi, .flv, .m4v, .mov, .mp3, .mp4, .rm, .rmvb, .wma and .wmv
• Dynamic throttling adjustment based on:
  • The file types and their encoded bit rate
  • The available bandwidth of the connection
  • Default and maximum throttling rates
  • Concurrent connection limits
  • Target throughput rate for the site
• Throttling rules configurable at various levels including server, site and virtual directory
• Fast Start experience for optimal user experience
• Extensibility to enable other media formats and file types
• Better-together solution when combined with Web Playlists

Have a nice day! Alesandro

In the beginning, some c/p from IIS site:

IIS Application Warm-Up for IIS 7.5 enables IT Professionals to improve the responsiveness of their Web sites by loading the Web applications before the first request arrives. By proactively loading and initializing all the dependencies such as database connections, compilation of ASP.NET code, and loading of modules, IT Professionals can ensure their Web sites are responsive at all times even if their Web sites use a custom request pipeline or if the Application Pool is recycled.

Now, ME!

At first glimse you can say : “WOW” this extension rocks!!! I dont have to wait for my application to compile! My site will load much much faster!

And, imagine, you would be completely RIGHT! This is a great extension, but ( yeah, there’s a but ), I would NEVER install this extension on a shared hosting server! Why you ask?

Biggest reason is the WASTE of resources!

By preloading some site that has 5-10 unique visitors/day ( yes there are sites like that ), you are efectively wasting resources on the server. Imagine what would happen if you had around 500-600 applications on the server, all preloaded? How much RAM would the machine need to have to keep all those applications preloaded? I guess the answer is : A LOT!

So, conclusion, when to use IIS Application Warm-Up?

Use it on your own machine! When you have a dedicated machine just for 1-2 websites.  You, and your users will benefit from preloaded applications. Everything will open more faster!

If you have a shared hosting machine, MY reccomendation is to NOT use the IIS Application Warm-Up extension!

Well…in the very beginning, my answer is pretty much simple : yes AND no!  Why you ask?  Just keep reading…

Compression, regardless if its the compression of static or dynamic content is using CPU – that is a fact we can all agree upon.

Lets say compression is a tradeoff – CPU for bandwidth..use more cpu to “burn” less bandwidth.

The big question here is how to decide if you will benefit from turning on compression or not.

Most of us have “multi-purpose” servers which run various roles at the same time ( database server ( MYSQL , MSSQL, etc…) , mail server, web server, etc.. and all of those services are spending a certain amount of CPU time.

By turning on the compression, you will automatically “lose” some CPU time which could have been used for faster execution of some database queries i.e…

This is the key problem in our case. Is your machine powerfull enough to handle all the services it is already running + compression? Because in the end, you could end up with an even slower server!!!

If you have a small server ( 1 x quad core cpu, 4-8 gb ram ) which is under heavy or moderate load and you want your applications to be “jumpy” ( i.e : fast editing of some articles in your favourite CMS system ),  or you have lots of queries on your database service: DONT use compression, save your CPU time.  If you have some CPU time to spare,  turn on compression of static content which doesn’t change a lot or only needs to be downloaded every once in a while ( browser cache expires )

In case you have a big machine ( 2x quad core nehalems, 24 gb ram, 4x enterprise level hdd’s with hw raid controller, etc…)  and you have CPU time to spare, by all means, turn on the compression of both static and dynamic content. You will notice great improvements on your bandwidth costs

In my experience, the biggest bottleneck on 99% of the server is the disk system. Ofcourse, in my case we are talking about some small RAIDs with 4-8 disks.

Great example of that case are these two pictures:

CPU usage on a 2xQUAD core server with 16 gb of RAM.

As we can see, the server peaks out at 28% of cpu usage, which means it has lots of CPU time to spare for compression.

However, lets have a look at its disk system:

As we can see on the graph, average DISK FREE TIME is 64%, which is a bit low for my personal taste. I would be much more comfortable that this number is around 70 -75% .

This machine would definatelly benefit from turning on compression, since it has lots of CPU time to spare.

But I own a small server…is there any hope for me???

NEVER FEAR IIS 7 IS HERE!!!

One great feature in IIS 7 and IIS 7.5 is that it  offers CPU roll-off function.  When CPU usage goes  above certain level you set,  IIS server will stop compression and when usage drops below the level you have set up, it will start compressing content again.  This function is controlled by the staticCompressionEnableCpuUsage and dynamicCompressionDisableCpuUsage attributes.

For the owners of smaller machines, this function is just AWESOME! It will save you from unpleasant suprises like getting a call at 2-3 AM with a complaint that the SQL server is very sloooow.

In the end; you be the judge. Will you turn on compression on your server or not? Let me know…