Jun 27, 2011

Easy Software RAID 1 With XenServer 5.6

I finally got my virtualization servers in, and all of my components to get them humming with XenServer 5.6 Sp2. The only problem I found was that the onboard RAID controller on my SuperMicro SuperServer 6016T-MTLF is really a HostRAID or FakeRAID solution. That's a problem because according to Citrix, XenServer does not support FakeRAID. Ain't that a bitch?

XenServer does support software RAID though using Linux mdadm. That is good news because to get two supported hardware RAID controllers I would have to fork over another $400, and I am already $400 over budget because my SuperMicro vendors didn't get me the right RAM. That is a different story though...

Anyway, I found an interesting tutorial on how to configure software RAID 1 in XenServer.  I am cool with using software RAID 1 in Linux as I have never had problems with it. I find Linux software RAID is pretty stable. Plus since it's only RAID 1 I am unlikely to see a huge performance hit.

Citrix XenServer 5.6 logoThe only problem with the tutorial I found is that it takes a lot of terminal commands to get software RAID configured properly, and if I have to do this on more than one server that would be a pain. So I decided to copy all the commands into one handy dandy shell script! You can download that sucker here: (XenServer RAID 1 Script)

In order to run it, you must have two hard drives of the same size. Run the XenServer install like normal, and only select the SDA drive as the installation point, as well as for the VM containers. Make sure that you leave SDB unchecked when configuring your VM containers. After that, follow the prompts like normal to complete the install.

Once the install is done, you can ssh into your newly installed XenServer from another machine, then run the following:

  • wget http://ftp.bauer-power.net/misc/XenRAID/xenRAID.sh
  • chmod +X xenRAID.sh
  • sh xenRAID.sh

That's it pal! Just wait a few minutes, answer a few questions with 'Y' for yes, and you will have a software RAID 1 implementation of XenServer 5.6 is no time! I have tested it three times in a row, and it works great! I have also taken out one drive at a time to verify that XenServer still boots, and it's worked flawlessly!

If you do have a hard drive failure, I found a really good tutorial on how to rebuild your RAID array here: (How to rebuild software RAID 1 in Linux)

Do you already use Software RAID on your XenServer? Had any issues? Let us know about your experiences with it in the comments.

Via [Tech-Stuff]

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Jun 20, 2011

Download GoTo Meeting Client Without Registration

Sweet damn if there is one thing I hate almost more than anything on the Internet is being forced to register my information just to download a piece of software. Especially if said software is free, or if I have previously purchased said software. I get it though, you Marketing weenies need to collect information about potential leads so you can make a sale. I am sure there are other ways of doing it without having to make every damn person who visits your site register.

Even worse than simply registering your name, address and email to get a free download, I hate when companies force you to register a credit card as well. You kno0w, so if you forget to cancel, or not order by a certain date they can automatically charge you. That's basically extortion if you ask me, and i am pretty sure that extortion is illegal.

Anyhoo, the latest company to get under my collar is GoTo Meeting which is not owned by Citrix. My company already has a number of GoTo Meeting accounts, however while re-imaging a user's laptop I had a hard time locating the install media for the client. No problem I told myself, I will just download it from the GoTo meeting website. That's where I got hit with the registration bull shit!

Well, as you can tell I'm a little bitter today about this. Sure it's not a big deal, but it really chapped my hide, so I decided to download the installer and make it available via my FTP server. You can go ahead and download that bad boy here: (GoTo Meeting Client Download)

Now you will still have to have a GoTo Meeting License to use it, and if you are new to GoTo Meeting, you will still have to register for a trial account to get started here: (New user registration)

If you already have an account though, and don't feel like re-registering, or calling some customer service rep just to get something you already own, then feel free to use my bandwidth to download the client from the link above!

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Jun 14, 2011

Seriously, I've decided on a virtualization technology!

If you are a regular reader of Bauer-Power, first of all thank you, second of all you know I've been fiddling with an alternative virtualization platform to VMware ESXi. The main reason being I wanted certain features that VMware ESXi just doesn't support with it's standard free version. Features like clustering and vMotion.

At first I started playing with Proxmox VE, which looked really promising. It is a free, open source hypervisor that uses KVM. It was okay, but it was quirky and kind of a pain in the butt some times. I thought screw it, I'll just setup VMware ESXi in a shabby manual failover configuration and it would be good enough.

Right after writing my article about using ESXi, a reader by the name of Davis asked if I tried XenServer. I hadn't tried it at all. The last time I looked into XenServer the free version wasn't much better than ESXi. Apparently while we were all sleeping though, Citrix decided to release a bunch of cool features in their free version! Some include central management with XenCenter, XenMotion, and clustering! Hallelujah! Just what the doctor ordered!

Here is a list of features you get in the free version from the Citrix website:

  • XenServer hypervisor
  • IntelliCache
  • Resilient distributed management architecture
  • VM disk snapshot and revert
  • XenCenter management
  • Conversion tools
  • XenMotion® live Migration

Plus, the look, feel and functionality of XenCenter is almost just like vSphere!

While I'm waiting on my new servers to set my virtualization environment up on, I setup a test XenServer environment using two Dell Vostro 1500 laptops. Yes, XenServer ran on two laptops! I then joined the two servers into one resource pool or cluster, and added a shared iSCSI LUN from my Buffalo Terastation. After that I setup a Windows XP VM, and installed the XenServer tools to test XenMotion, or live migration. Guess what? It worked like a mutha flippin' charm! Check it out!

Like Proxmox, XenServer has the drawback of not being able to thin provision VM's stored on a shared iSCSI LUN. This isn't a huge issue if your SAN supports thin provisioning on the back end. Higher end SANs like EMC, Compellent and NetAPP support this. Buffalo Terastations, and OpenFilers however do not. Still, not a deal breaker though. I figure since I'm using cheap storage that it wouldn't be too hard to get my boss to let me buy more when I use up 6TB.

Are you using XenServer in your environment? Do you use the more expensive Enterprise or Platinum versions? How do you think it compares to VMware? How about Hyper-V? Let me know what you think of this setup in the comments!

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Jun 13, 2011

Poor Man's VMware Failover Setup

Greetings everyone. I am writing up this post sort of as a retraction on my post about Proxmox VE that I wrote about a week or so ago. If you didn't get a chance to read it I talked about how I was going to setup a Proxmox VE virtualization cluster for my new company. After playing with it for the last few weeks, I decided to abandon that idea.

Some of the things I didn't like about Proxmox was that if I wanted to use shared iSCSI storage for live migrations the way it is designed, I couldn't do any thin provisioning. Also, although there are several methods for converting physical servers to virtual servers, the process is usually a multi-step process that take a lot of time to complete. I decided it just wasn't worth it, and decided to go back to plan A which was to setup two ESXi servers with shared storage.

So here's my plan, I purchased two SuperMicro SuperServers with dual quad core processors and 48GB of RAM each. I also bought an 8TB Buffalo iSCSI NAS for shared storage. Actually, it's only 6TB after I configure RAID, but that should be enough. The Buffalo NAS does run SATA drives, but that is okay because nothing in our home office is very resource intensive, so SATA should be fine. The equipment cost around $6,000. Not too expensive, which is good because we have very little IT dollars in our budget.

What I will do is install ESXi on both SuperServers. I will then P2V all the junky servers I have in the home office to one or the other nodes in my poor man setup. I will then make sure to register each VM on the other node. So basically each node will have the same VMs registered on them. Then I will power on half of the VMs on one node, and power on the other half on the other node. This way if something happens with one node. I can easily power the servers on the other node with minimal down time.

This setup, although it lacks cool features like vMotion, DRS, and HA, does give me a method for rather quick manual failover. Also, for simple tasks like rebooting, powering on, and shutting down servers etc, I can use the free version of Trilead's VM Explorer tool to manage the VM's on both nodes at the same time.

What do you think about my plan? Do you have a similar setup at your company due to budget constraints? How is it working out for you? Do you have any other suggestions? Let me know in the comments.

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Jun 10, 2011

How To Sync Domain Passwords With Microsoft Online

I have mentioned in previous posts that at my new company we are using Microsoft's Business Productivity Online Services or BPOS for short. It's basically Microsoft's own hosted Exchange service but also includes OCS, SharePoint and Live Meeting. It's a pretty cool solution for small businesses and is actually way more cost effective than running your own Exchange server, SharePoint server etc.

So the problem with Microsoft Online is that with their current version their hosted solution is completely separate from your active directory. Now, they do have a tool where you can sync AD accounts, but that's where it stops. The passwords are different, aliases, groups etc are all different. They also have their own password expiration policy so it is really easy for users to get out of sync and have to start using two passwords. One for AD services, and one for Microsoft Online.

 A company by the name of MessageOps has developed a free tool that allows for password syncronization from active directory to BPOS. The tool is called MessageOps Microsoft Online Password Syncronization. To set it up is really easy, just do the following:

  • Install the Client Service on all your domain controllers, and point them to the Password Sync Server
  • Install the Password Sync service on a 32bit member server
  • Install the Microsoft online Migration Tools on the Password Sync Server
  • Open Services.msc and change the logon for the Password Sync service to use a domain user account
  • On the Powershell tab of the Password Sync tool, use your Microsoft Online Service admin account credentials
  • Make sure you login to the server as the domain service account once, and open Internet Explorer (Don't ask)

MessageOps BPOS Password Sync

    That's it, now when a user changes their password, the client service on the domain controllers will pick up the change and send the new password encrypted to the Password Sync server. From there the Password Sync server will create an encrypted session with Microsoft Online and verify the user exists. I the user exists, then the password will be updated on BPOS as well! BOOM!

    Microsoft BPOS will soon be called Office 365 which will include features based on Microsoft's 2010 product line, and will also include active directory federation. Until then though, you can can use the free tool from MessageOps!

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    Jun 7, 2011

    Setting Up A HAProxy Failover Cluster

    So it looks like I am going to get some time to write about my setup after all. If you read my post yesterday, I recently setup a failover load balancing cluster for my company’s public web servers. My previous company did something similar with two F5 Big-IP appliances for about $90,000 or so. I however did it completely for free using Ubuntu Linux and HAProxy!

    I mentioned in my post yesterday how to install HAProxy on Ubuntu 11.04, and what you need to do to get it to start correctly at boot up. Today I am going to tell you how to add a second HAProxy server, and configure failover using Keepalived.

    • Stand up two identical Ubuntu servers and install HAProxy using my instructions here: (How to Install HAProxy)
    • Configure your /etc/haproxy/haproxy.cfg file on Node1, and copy to to Node2 using scp sudo scp /etc/haproxy/haproxy.cfg root@node2:/etc/haproxy/       
    • Install Keepalived on both servers  sudo apt-get install keepalived   
    • On both servers edit the /etc/sysctl.conf with your favorite text editor (i.e. sudo nano /etc/sysctl.conf) and add the following at the bottom of the file so HAProxy can bind with our virtual IP address(es).  net.ipv4.ip_nonlocal_bind=1
    • Run sudo sysctl –p
    • Run sudo nano /etc/keepalived/keepalived.conf to create your Keepalived configuration, and paste in the following, make sure to change the IP address to match your VIP (Virtual/shared IP address):  
      vrrp_script chk_haproxy {           # Requires keepalived-1.1.13
              script "killall -0 haproxy"     # cheaper than pidof
              interval 2                      # check every 2 seconds
              weight 2                        # add 2 points of prio if OK
      vrrp_instance VI_1 {
              interface eth0
              state MASTER
              virtual_router_id 51
              priority 101                    # 101 on master, 100 on backup
              virtual_ipaddress {
              track_script {

    • Do the same on Node2, but change the priority to 100 to make Node2 the slave.
    • Run the following to start Keepalived:   sudo /etc/init.d/keepalived start   
    • Run the following on Node1 to check to make sure it is listening to your virtual IP address (VIP/Shared IP):  ip addr sh eth0   
    • Start Keepalived on Node2, and run the command above to make sure Node2 is NOT listening to the VIP.
    • If it’s not running already, start HAProxy on both servers by running the following:

      sudo /etc/init.d/haproxy start

    • To test, you can run a constant ping on the VIP and reboot Node1, you should only see one dropped packet if done correctly.
    Pretty cool right? One thing to node is that you can have your HAProxy cluster server load balancing to more than one server farm, with multiple IP’s. Just add the multiple VIPs to your /etc/keepalived/keepalived.conf file. For instance, lets say you have to IP’s you want to act as VIPs for two sets of web servers. One VIP is going to be and the other is going to be then add the two IP’s to your config in the virtual IP section like so:

    virtual_ipaddress {

    If you have to add more IP’s later, you can do so and simply restart the Keepalived service. As far as how to create an HAProxy config file, I am going to let you look that up on your own. There are many different settings you can configure for HAProxy including both HTTP modes and TCP modes. I will tell you that I am using HTTP mode for port 80 HTTP traffic, and TCP mode for HTTPS/SSL traffic.

    What do you use for load balancing? An appliance like Netscaler, or F5? Maybe an open source option like Pound that provides SSL offload? Let me know what you use and why in the comments.

    Via [HowtoForge]
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    Jun 6, 2011

    How To Install HAProxy on Ubuntu 11.04

    Happy Monday everyone! I have a pretty good one to share with your today. Over the weekend I stood up an open source load balancer running on Ubuntu Linux and running a free tool called HAProxy. I was originally going to use another load balancing platform called Pound that also does SSL offload, but I decided against it because it would require me changing the way my company’s firewall is configured to ensure that the sites that need to be secured, stayed secured.

    I decided to go with HAProxy not just because it is simple in that it can load balance anything, including SSL encrypted sites, but because it doesn’t natively do SSL offload on its own, and lets the web servers handle that. With HAProxy I was able to stand it up in our existing environment without having to change a damn thing on the firewall.

    So why the write up on how to install it? I mean, it’s available in the repositories right? Yes it is, but after installing it there are a couple of things you need to do to make sure it starts up when you reboot, especially on Ubuntu 11.04.

    haproxySo here it is, how to install HAProxy:

    • Run sudo apt-get update
    • Run sudo apt-get install haproxy
    • After the install, run sudo nano /etc/default/haproxy and change ENABLED=0 to ENABLED=1 and save it

    Normally, you can stop here, but for some reason in Ubuntu the /etc/init.d/haproxy script tries to start before networking and fails. To fix that run the following:

    • sudo update-rc.d -f haproxy remove
    • sudo update-rc.d -f networking remove
    • sudo update-rc.d haproxy start 37 2 3 4 5 . stop 20 0 1 6 .
    • sudo update-rc.d networking start 34 2 3 4 5 .

    What that does is changes the order of the startup scripts so that Networking has a chance to start before HAProxy. After that you can reboot all you want and HAProxy will start right back up.

    I am going to try to find time to write more about my HAProxy setup sometime this week (Maybe tomorrow). It’s pretty cool, and it is allowing me to load balance four webservers each with a mix of SSL HTTPS and standard port 80 HTTP traffic.

    Via [Ubuntu Bugs]

    Jun 3, 2011

    Recovering Deleted Offline Files in Windows 7

    I haven’t had to write too much about desktop related issues recently. I’ve been mainly involved with higher level systems for the past few years, but in my new gig since I am the only IT person I have to do everything including Desktop support.

    Well I got hit up by a pretty frantic user yesterday. Apparently for the last two weeks they were working on a bunch of documents in their offline file cache and didn’t realize it. Something happened and all of a sudden their cache got wiped out and everything they were working on disappeared. Holy crap right?

    I went to look at their sync center in Windows 7 to see if I could browse their offline files, but they were gone. I had never really dealt with a situation like that, so of course I hit up Google. It turns out that Windows 7 saves your offline file cache to C:\Windows\CSC\v2.0.6. If you try to go in their you will get an access denied notice. It doesn’t matter if your are an administrator or not. The only way to take ownership of this particular file is to run the takeown command from command line:

    takeown /f c:\windows\csc /r /a

    Windows Security_2011-06-03_11-44-43After that you can get in, but guess what, his cache was completely empty. Flipping awesome! I right clicked on CSC and looked at previous versions, sure enough there were versions from the day before, but when I tried to restore the previous versions I would get access denied errors! Damn it! I even tried modifying the permissions in the previous version folder to take ownership, and couldn’t do that!

    After a while of Googling around and seeing nothing, I decided to shoot for the stars and try my old free buddy Recuva. Guess what? Recuva was able to restore about 5000 documents from the users cache!


    After scanning the hard drive for missing documents, I sorted the results by file path. I restored everything I saw in C:\Windows\CSC to a network share. The user is happy, I’m happy, the issue is resolved.

    Have you run into this before? Were you able to recover the files? How did you do it? Is there an easier way? Let me know in the comments.

    Jun 1, 2011

    How To Create a HA Active/Passive Openfiler Cluster

    Greetings fellow geeks! If you have been following along with me, I am thinking about changing SAN technologies in the office. The reason being is cost savings, pure and simple. Right now we have a NetApp FAS2020 which goes for $24,000. We are starting to run low on disk space, and instead of forking over another $24,000 I felt I could get something that does what we need for less.

    Enter Openfiler ESA. For those that don’t know, Openfiler is a free and open source NAS/SAN operating system that runs on Linux. It can act as a simple file server, or if you want you can configure it as an iSCSI, or even a Fibre channel SAN. Not only that, but what sets it apart from other free NAS operating systems like FreeNAS is that you can actually configure Openfiler in a HA Active/Passive cluster for redundancy. Hell, you can even configure it for offsite replication for disaster recovery!

    So here is my plan, I want to get two SuperMicro storage chassis with hardware RAID controllers. I will configure each chassis with hardware RAID 5. Then I will create a software network mirror of the two nodes using the HA setup for Openfiler using DRBD, Corosync and Pacemaker.

    Here is a drawing of my plan to give you a visual:


    I am not going to write out the full how-to because it is kind of a lengthy process. I will however direct you to the how-to I used in my test environment that worked out really well here: (Cluster Openfiler)

    I will point out some things that I felt the author left out, or didn’t explain though:

    • Your Meta partition only needs to be 512MB, however your Data partition needs to be the full size of the storage you want to use for your SAN. I created my partitions using cfdisk. They must be logical partitions. Also, your data partition needs to be an LVM which is type 8e in cfdisk/fdisk. It’s important that you don’t create these partitions during the installation!
    • In the section where you create your LVM filter, the file you want to edit is /etc/lvm/lvm.conf

    Other than that, I think the how to was pretty informative, and well written. If you follow it exactly, you should have your HA setup in no time!

    Have you ever setup an Openfiler cluster? How do you like the performance? If you’ve setup an Openfiler cluster, have you ever used another SAN technology? how do you think it compares? Let me know your opinion in the comments!


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