Category Archives: Windows server 2012

Get e-mail alert for failed logon attempt on Outlook Web Access (OWA)

Just for fun I tried to establish a mechanism that will allow me to get information for failed logon attempt on Outlook Web Access (OWA).

If you open event viewer on your CAS server (where OWA is located) you can find out that failed requests are logged with Event ID 4625.
003

001
In general information you can find interesting things like – username which was used and IPv4 or IPv6 address from where the attempt was made.
002
All you need to do is to Attach task to this event
004
As all other actions are deprecated you should use the option to Start a program – here we will run a Powershell script to do the job.
005
We need to create a PS1 (powershell script) with content:

$EventMessage = get-winevent -FilterHashtable @{Logname=’Security’;ID=4625} -MaxEvents 1 | fl TimeCreated, Message
$eventmessagetstring = $EventMessage | Out-String
$EventMessageAccountNameText3array = $EventMessagetstring | Select-String -Pattern “Account Name:\s+\S+” -AllMatches | Select -ExpandProperty matches | Select -ExpandProperty value
$EventMessageAccountNameText3 = $EventMessageAccountNameText3array[-1]
$EventMessageAccountNameText = $EventMessagetstring | Select-String -Pattern “Failure Reason:\s+\S+\s+\S+\s+\S+\s+\S+\s+\S+\s+\S+” -AllMatches | Select -ExpandProperty matches | Select -ExpandProperty value
$EventMessageAccountNameText2 = $EventMessagetstring | Select-String -Pattern “Source Network Address:\s+\S+” -AllMatches | Select -ExpandProperty matches | Select -ExpandProperty value

$EmailTo = “admin@domain.com”
$EmailFrom = “alert@domain.com”
$Subject = “OWA attack from $EventMessageAccountNameText2”
$Body = “Owa attack from: `n $EventMessageAccountNameText2 `n $EventMessageAccountNameText3 `n $EventMessageAccountNameText”
$SMTPServer = “IPOfYourSMTPServer”
$SMTPMessage = New-Object System.Net.Mail.MailMessage($EmailFrom,$EmailTo,$Subject,$Body)
$SMTPClient = New-Object Net.Mail.SmtpClient($SmtpServer, 25)
$SMTPClient.Send($SMTPMessage)

So in task properties we should choose:
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In Add arguments (optional) field we should add:

-ExecutionPolicy ByPass -File X:\PathToScript\OwaAttack.ps1

So if everything is correct – next time someone fail to enter correct password or an attack on OWA is performed you will get an e-mail like this:

006

How to monitor “unmonitorable” stuff on Windows server with PRTG Network Monitor

I really love PRTG Network Monitor, simple and efficient monitoring solution I have been using for many years… It has a lot of sensors that you can use to monitor various stuff – from network devices to storage devices, to some predefined WMI sensors for disk monitoring on Windows …
But there are some things that are not that simple to monitor… For example DNS server cache entries… Or, DHCP server leases in use? There is no predefined sensor in PRTG to do that – but there is something very nice and useful – it is called: HTTP content sensor

http-content

This sensor can “read” the numeric value from HTTP page (even more than one (so you can have multiple channels = multiple lines in single graph for similar stuff))…

So… The challenge to get from this list:
show-dnsservercache
to:
graph

Let’s do it:
1. Let’s somehow get from that list (Show-DnsServerCache) to numeric value in PowerShell
2. Publish result on some web server (could be IIS on the same server)
3. Schedule PowerShell script to run (every 1 minute) to get the value
4. Collect result with PRTG HTTP Content sensor

1 (and 2). Create PS1 script (by using PowerShell ISE or maybe Visual Studio Code or just by using Notepad :)):

$dnsservercache = Show-DnsServerCache
$dnsservercache = $dnsservercache.Count
$dnsservercache = “[” + $dnsservercache + “]”
$dnsservercache = $dnsservercache.Replace(” “,””)
$dnsservercache | out-file -Encoding utf8 C:\inetpub\wwwroot\dnsservercache.txt

In that (dnsservercache.txt) TXT file you should find something like (number may be different): [13863]

In this case I am “publishing” TXT file on IIS server on the same server – you should write file somewhere else if web server is not running locally.

3. Schedule Powershell script to run every 1 minute to get value
Just create basic task in Task Scheduler, choose Start a program and fill the form:
Program/script: PowerShell.exe
Add arguments: -ExecutionPolicy Bypass C:\ps\Stats.ps1
Start in: C:\ps

When you finish creating task you should modify it to run every one minute here:

schedule

4. Collect value from website / txt file

In PRTG you can now create new sensor by choosing HTTP Content and just fill the form like this:
http content2

In a couple of minutes you should get this beautiful graph:

graph2

graf day 2

IPv6 in Windows environment for beginners

Currently I am working on implementing dual-stack (so all servers and computers will run on IPv4 and IPv6 at the same time) in Windows envrironment with Active directory domain controlllers, other member servers (file server, DFS, SharePoint services…), Exchange server 2013, Lync/Skpye for business…

Purpose of this post is to walk you through the obstacles and difficulties while implementing both protocols to work together…

So basicaly we need to know the folowing:

We have one (or more) public IPv4 addresses which we NAT in our private networks where we have our servers…
Our providers gives us some IPv6 prefix for “wan” interface of our router and over that there is a routed prefix which we will use internaly (you need to know there are public – or globaly routed IPv6 addresses inside your network – SO TAKE CARE of your Firewall roules (We will cover that later)).

Simple steps to implement dual stack is to:

a. Get IPv6 from your provider
b. Have a router that understands IPv6 🙂
c. Configure router advertisment on internal network with M (managed (this will force users to use DHCPv6 instead of autoconfiguring IPv6 (SLAAC)) and O (other configuration (this will point clients to DHCPv6 server to get DNS servers (your domain controllers IPv6 addresses)) flag
d. Configure DHCP server on your Windows server with DHCPv6 parameters (prefix, exclusions, DNS servers (called: 00023 DNS Recursive Name Server IPv6 Address)
e. disable DHCP client on servers that use static IPv4/IPv6 addresses (if you do not do that your servers will autoconfigure additional IPv6 addresses as told by RA…) You can use Powershell: Set-NetIPInterface –InterfaceIndex <number> -Dhcp Disabled

Shared nothing live migration from Windows server 2012 to Windows server 2012 R2

While we are waiting for Windows server 2012 R2 I just played with a feature that will come very useful after upgrading Hyper-V hosts to new version (R2). Microsoft did a great job with the possibility to live migrate (by using shared nothing live migration feature that was already available in Windows server 2012) from old Windows server 2012 hosts with Hyper-V to new Windows server 2012 R2 hosts with Hyper-V. So you will have zero downtime while upgrading your virtualization platform. This goes one way only – so only from older (Windows server 2012) to Windows server 2012 R2 and NOT vice versa.

Here is a video how it works – at the end I also demonstrated that it does not work in opposite direction.

http://screencast.com/t/yz0ggCbFki

Update: It will fail if you have different name for virtual switch – If you have a new name for virtual switch on new server I suggest that you create an “fictive” private virtual switch with the same name on original (old hyper-v). You are not able to choose virtual switch on destination.

“Demystifying” – Windows server 2012 Hyper-V 3.0 network virtualization – part III – (two hosts / two subnets)

In this part III I would like to show you how network virtualization works between two Hyper-V hosts in different subnet (in my example connected HV01 – Router (IPSec VPN) – WAN – WAN – Router (IPsec VPN) – HV02).

You can see how to do that by clicking on a link to video tutorial:
http://www.screencast.com/t/pRDC7Z4UKrg  – Hyper-V 3.0 – Network virtualization Part 4

* at 1:48 – I have already copy pasted that before – you should do it on both hosts
* at 2:04 – there is mistake as those parameters were already there so I removed them and resumed with video recording
* at 2:43 – I did not paste the second part to HV02 (I already did that in previous demo)
* at 3:59 – You will not see GRE traffic until you add Ethernet card to monitoring

In my environment I have two hyper-v hosts called HV01 (10.17.217.177 with gw 10.17.217.1 (router – that makes IPSec VPN)) and HV02 (10.17.218.177 with gw 10.17.218.1 (router – that makes IPSec VPN)).

So only Hyper-V hosts “see” each other over VPN (two different subnets).

I have used folowing powershell cmdlets:

First we need to enable ms_netwnv component on !PHYSICAL! nic – not on virtual switch NIC!
Run it on HV01 and HV02:

Enable-NetAdapterBinding “Ethernet” -ComponentID ms_netwnv

Now we create Lookup record and CustomerRoute (we use IP addresses of our virtual machines, their mac address and IP address of Hyper-V host) This is explained in my previous post.
Run it on HV01 and HV02:
New-NetVirtualizationLookupRecord -CustomerAddress “10.10.10.11” -ProviderAddress “10.17.217.177” -VirtualSubnetID “5001” -MACAddress “AAAAAAAAAA01” -Rule “TranslationMethodEncap”
New-NetVirtualizationLookupRecord -CustomerAddress “10.10.10.12” -ProviderAddress “10.17.218.177” -VirtualSubnetID “5001” -MACAddress “AAAAAAAAAA02” -Rule “TranslationMethodEncap”
New-NetVirtualizationCustomerRoute -RoutingDomainID “{11111111-2222-3333-4444-000000000000}” -VirtualSubnetID “5001” -DestinationPrefix “10.10.10.0/24” -NextHop “0.0.0.0” -Metric 255

Now only on HV01 you should configure provider address and provider route (this is how hosts will get connectivity to each other…):
New-NetVirtualizationProviderAddress -InterfaceIndex 12 -ProviderAddress “10.17.217.177” -PrefixLength 24

New-NetVirtualizationProviderRoute -InterfaceIndex 12 -DestinationPrefix “0.0.0.0/0” -NextHop “10.17.217.1”

The same thing on HV02:
New-NetVirtualizationProviderAddress -InterfaceIndex 12 -ProviderAddress “10.17.218.177” -PrefixLength 24
New-NetVirtualizationProviderRoute -InterfaceIndex 12 -DestinationPrefix “0.0.0.0/0” -NextHop “10.17.218.1”

At the end we need to add VirtualSubnetID parameter to our VM’s sitting on HV01 and on HV02

HV01 (Where Blue01 VM sits):
Get-VMNetworkAdapter -VMName Blue01 | where {$_.MacAddress -eq “AAAAAAAAAA01”} | Set-VMNetworkAdapter -VirtualSubnetID 5001

HV02 (Where Blue02 VN sits):
Get-VMNetworkAdapter -VMName Blue02 | where {$_.MacAddress -eq “AAAAAAAAAA02”} | Set-VMNetworkAdapter -VirtualSubnetID 5001

“Demystifying” Windows server 2012 Hyper-V 3.0 network virtualization – part II (two hosts / same subnet)

Today I was presenting @ bleedingedge.si conference… My session was about Windows server 2012 / Hyper-V 3.0 network virtualization.

 

I have recorded this sequence of commands so you can see the configuration and how it works:

http://www.screencast.com/t/wsDAKpKumlSm – Hyper-V 3.0 – Network virtualization Part 1

http://www.screencast.com/t/q3G9SViY6gId – Hyper-V 3.0 – Network virtualization Part 2

http://www.screencast.com/t/bxOznDklp – Hyper-V 3.0 – Network virtualization Part 3

 

In my demo environment I have:

Two Windows server 2012 with Hyper-V 3.0 role installed

HV01 / Only one network card so it is used by VMs and host (management) with IP 172.31.200.11
HV02 / Only one network card so it is used by VMs and host (management) with IP 172.31.200.12

On each host there are TWO virtual machines:

On HV01 there are:

– Blue01 (10.10.10.11 with STATIC MAC*address AAAAAAAAAA01)
– Red01 (10.10.10.21 with STATIC MAC*ddress CCCCCCCCCC01)

On HV02 there are:

– Blue02 (10.10.10.12 with STATIC MAC*address AAAAAAAAAA02)
– Red02 (10.10.10.22 with STATIC MAC*address CCCCCCCCCC02)

*You should DEFINE STATIC MAC on Virtual Machine network configuration – you must not use dynamicaly assigned MAC address (System center Virtual machine manager 2012 SP1 will do that for you automaticaly)

By defalt all machines are able to ping themselfs… We want to isolate Blue network so only Blue01 and Blue02 can ping each other and Red network so only Red01 and Red02 can ping each other.

First thing we need to do is to enable ms_netvm component on PHYSICAL NIC! (not on virtual switch created NIC!)
Enable-NetAdapterBinding “Ethernet” -ComponentID ms_netwnv

Second thing is that we need to create Lookup records on both Hyper-V servers. You should copy/paste this script on both hosts:
New-NetVirtualizationLookupRecord -CustomerAddress “10.10.10.11” -ProviderAddress “172.31.200.11” -VirtualSubnetID “5001” -MACAddress “AAAAAAAAAA01” -Rule “TranslationMethodEncap”
New-NetVirtualizationLookupRecord -CustomerAddress “10.10.10.12” -ProviderAddress “172.31.200.12” -VirtualSubnetID “5001” -MACAddress “AAAAAAAAAA02” -Rule “TranslationMethodEncap”

Then you need to create Costumer Route – on both Hyper-V hosts:
New-NetVirtualizationCustomerRoute -RoutingDomainID “{11111111-2222-3333-4444-000000005001}” -VirtualSubnetID “5001” -DestinationPrefix “10.10.10.0/24” -NextHop “0.0.0.0” -Metric 255

Then you need to add provider address to PHYSICAL NIC – you need to find out interface index by using get-netadapter!

In my example on HV01:
New-NetVirtualizationProviderAddress -InterfaceIndex 12 -ProviderAddress “172.31.200.11” -PrefixLength 24
New-NetVirtualizationProviderRoute -InterfaceIndex 12 -DestinationPrefix “0.0.0.0/0” -NextHop “172.31.200.1”

and on HV02:
New-NetVirtualizationProviderAddress -InterfaceIndex 12 -ProviderAddress “172.31.200.12” -PrefixLength 24
New-NetVirtualizationProviderRoute -InterfaceIndex 12 -DestinationPrefix “0.0.0.0/0” -NextHop “172.31.200.1”

When this is done we need to configure VirtualSubnetID on virtual machines:
On HV01 (where Blue01 vm is running) we should do:
Get-VMNetworkAdapter -VMName Blue01 | where {$_.MacAddress -eq “AAAAAAAAAA01”} | Set-VMNetworkAdapter -VirtualSubnetID 5001

and on HV02 (where Blue02 vm is running) we should do:
Get-VMNetworkAdapter -VMName Blue02 | where {$_.MacAddress -eq “AAAAAAAAAA02”} | Set-VMNetworkAdapter -VirtualSubnetID 5001

Now network virtualization will take place and Blue01 will only be able to ping Blue02 and vice-versa. Red01 and Red02 are outside this VitualSubnet. In video you can see network monitoring where you can detect GRE network between hosts.
In video I also do live migration so I move Blue02 machine from HV02 to HV01 so you can see that network virtualization is aware of live migration and moving machines between HV hosts in the same network or also cross premise… I will cover that in next part! 🙂

Let’s virtualise!

Hyper-V 3.0 resource metering…

If you are hosting or if you just want to get the idea how is your Windows server 2012 with hyper-v role or hyper-v 3.0 server utilised you can use the hyper-v 3.0 resource metering powershell cmdlets…

First you need to enable metering on your host:

Get-VM -ComputerName hv01 | Enable-VMResourceMetering

Then you can choose the VM that you want to get info for:

Get-VM -ComputerName hv01 -Name VMName | Measure-VM

or differently formated:

Get-VM -ComputerName hv01 | Measure-VM | Sort-Object -Property AverageProcessorUsage -Descending | Select-Object -First 5 -Property ComputerName,VMName,AverageProcessorUsage

More commands you can find on:

http://csharpening.net/?p=967

But that’s “ugly” output 🙂 if you want to have nice graphical view of your stats you can use freeware:

http://poshstats.net/ – great software!

Lets meter!