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Installing Linux Integration Services v2.1 on Red Hat ES 5

Posted on August 31, 2010 by Sam T

Ok, so I got the task to install the Linux Integration Service for Hyper-V R2 on a RedHat Enterprise Server 5. Something that turned out to be a bit more to handle than I would have thought. So here’s a little How-To.

Preparations

Read the documentation provided in the Linux Integration Services download. Much of the information in this article is in there, but some parts are not. Otherwise I would not have bothered writing about it.

I’m not going to go through the OS installation process here, but make sure to select the “Software Development” packages since you will be needing it. In case you missed it, you can install them later by running these commands.

# yum groupinstall "Development Tools"
# yum install kernel-headers

I’m not actually sure that you need to run the kernel-headers install manually or if it’s included in the “Development Tools” package.

The first gotcha i ran into was the fact that the link to the Linux Integration Services–previously known as Linux Integration Components or LinuxIC–on RedHat’s information pages gave me a 404 and a redirect to a bing-search that returned the exact same 404. The page have simply been removed by Microsoft without any form of redirection to the new page. Anyway, a search on http://download.microsoft.com for “Linux Integration Components” do return the new page, and that’s where I learned about the new name.
Thank you for making it easy for us Microsoft!
Here’s a direct link to the search on the current name: http://www.microsoft.com/downloads/en/results.aspx?freetext=linux+integration+services&displaylang=en&stype=s_basic
And here’s a direct link to the actual download page: http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=eee39325-898b-4522-9b4c-f4b5b9b64551

This download contains an ISO file that you can mount using the Hyper-V- or VMM-console, or you can do as I did and download the ISO to the virtual machine, mount it locally, copy the files and unmount it. Like this.

# mkdir /mnt/ISO
# mount -o loop /root/LinuxIC v21.iso /mnt/ISO
# mkdir /opt/linux_ic_v21_rtm
# cp /mnt/ISO/* -R /opt/linux_ic_v21_rtm/
# umount /mnt/ISO

You probably have to be root to do this by the way.
With that done, let’s get to the installation.

Installation

As root, do the following:

# export PATH=$PATH:/sbin
# cd /opt/linux_ic_v21_rtm/
# make
# make install
# reboot

Why the export PATH command? Apparently, on RHES5, /sbin is not in the PATH by default and this is something that the make scripts are completely unaware of. The “make install” will try to run “depmod” which will fail since it’s not in the default path. You could also add “PATH=$PATH/sbin” to the root users ~/.bashrc which will put it back in the PATH but only for the root user, but I don’t know if that’s recommended.
And, yes. You DO have to reboot after the install.

If you are running RHES5 64bit you also have to install the “adjtimex” package. It is in the RHN repository but also on the RHES5 Installation CD in case you have no internet connection. Install it with yum like this:

# yum install adjtimex

And from the CD (mount it first) like this:

# rpm –ivh /mnt/cdrom/Server/adjtimex-1.20-2.1.x86_64.rpm

And that’s basically it for the installation.

Verification

How do you know that the driver are installed?

After the reboot, try running “modinfo vmbus” which should return something like this:

# modinfo vmbus
filename:       /lib/modules/2.6.18-194.11.1.el5/kernel/drivers/vmbus/vmbus.ko
version:        2.1.25
license:        GPL
srcversion:     3C1899C419665CB2514F2D0
depends:
vermagic:       2.6.18-194.11.1.el5 SMP mod_unload gcc-4.1
parm:           vmbus_irq:int
parm:           vmbus_loglevel:int

Try that with netvsc, storvsc and blkvsc too (replace the vmbus part) and you should get something similar. If you don’t, the installation did not succeed.
The documentation also tells us to check that the components are running with “/sbin/lsmod | grep vsc” which should return:

# /sbin/lsmod | grep vsc
blkvsc                 70184  3
storvsc                64264  0
netvsc                 73504  0
vmbus                  88304  3 blkvsc,storvsc,netvsc
scsi_mod              196953  6 scsi_dh,sg,blkvsc,storvsc,libata,sd_mod

The numbers will probably differ from installation to installation depending on blocksizes and allocation.

Configuration

Configuration is pretty straight-forward so I’ll keep this short.

When you install the drivers you will get a new network card called seth0, which I presume stands for Synthetic ETHernet. There’s nothing magic about it regarding configuration and “system-configuration-network” will work just fine.

The drivers will also give you a couple of SCSI-devices (if you have one attached) with the regular /dev/sd* naming. Simply configure these using fdisk or whatever GUI you might prefer.

There is also a note in the documentation about changing the grub configuration in the “Additional Information…” section. Do read that section.

Additional Comments

One thing I tend to do now that disk space is dirt cheap is to copy all ISO-files I use locally instead of mounting them when needed through Hyper-V. Simply because you can bet your insert-shorter-word-for-buttocks that the day you need it again, someone has been kind enough to have done som spring-cleaning or it’s locked by another machine in the cluster. If you have it locally and followed my instructions in the “Preparation” section, you will allready have a /mnt/ISO directory. Only thing you’ll have to do is

# mount -o loop /path/to/your.iso /mnt/ISO

And there you have it. Just remember to unmount it when you’re done.

I also almost never use the Hyper-V remote connection interface thingy since it will give you a GUI and the mouse just won’t work. If you haven’t configured a network card yet though, you could connect through Hyper-V and hit Ctrl+Alt+F1 to get a command prompt. Unfortunatly cut/paste don’t work here, but you could run system-configuration-network, assign an IP-address and then connect with an SSH client. I prefer PuTTY to a degree that I usually install the ported version on my Linux desktops aswell.

And I never logon using root. People should know this, but it should be stressed anyway. Always logon as regular user and su or sudo when needed. I can’t understand why RHES has root-login enabled by default in the SSH-server config.

Good luck!

Categories: Hyper-V, RedHat ES | Tags: How-To, Hyper-V, Linux, RedHat, RHES5

ESENT Error When Modifying OpsMgr Agent

Posted on March 19, 2010 by Sam T

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Getting “ESENT Kerys are required to install this application” when you are trying to modify/change an agent installation?

This seems to be most common on Windows 2008 and i guess it’s because of the UAC and the fact that opening the Control Panel isn’t running in administrative mode.

To work around this you need to run the msiexec command on the correct installation GUID from an administrative command prompt.

Besides running through the registry to find the GUID, one of the easier ways is this:

Open an administrative command prompt.
run wmic product
Locate your product by its name, the GUID (looks a bit like this {25097770-2B1F-49F6-AB9D-1C708B96262A}) directly after that is the one you want. Copy it.
run msiexec /i <PASTEYOURGUIDHERE>
Modify the agent as pleased

That’s pretty much it. Good luck.

Categories: OpsMgr 2007 | Tags: Errors, How-To, OpsMgr, Windows, Windows Installer, WMI

Linux Discovery – Not Enough Entropy

Posted on December 2, 2009 by Sam T

3 comments

Here’s a little trouble-shooting guide for discovering Linux systems from OpsMgr R2 when getting the following error from the wizard:

<stdout>Generating certificate with hostname="COMPUTERNAME"

[/home/serviceb/TfsCoreWrkSpcRedhat/source/code/tools/scx_ssl_config/scxsslcert.cpp:198]

Failed to allocate resource of type random data: Failed to get random data - not enough entropy

</stdout><stderr>error: %post(scx-1.0.4-248.i386) scriptlet failed, exit status 1

</stderr><returnCode>1</returnCode>

<DataItem type="Microsoft.SSH.SSHCommandData" time="2009-08-05T11:15:01.5800358-04:00" sourceHealthServiceId="0EB1D6DA-202C-7FC5-3D46-BDBB9208547D"><SSHCommandData><stdout>Generating certificate with hostname="COMPUTERNAME"

[/home/serviceb/TfsCoreWrkSpcRedhat/source/code/tools/scx_ssl_config/scxsslcert.cpp:198]

Failed to allocate resource of type random data: Failed to get random data - not enough entropy

</stdout><stderr>error: %post(scx-1.0.4-248.i386) scriptlet failed, exit status 1

</stderr><returnCode>1</returnCode></SSHCommandData></DataItem>

But first, a little background on the actual “problem”. To generate the certificate, the entropy needs to be high enough to generate random data for the certificate creation. Without the certificate, the OpsMgr agent won’t be able to open up communications with the MS. So, what creates this entropy we need? Bluntly put, a selection of hardware components that are likely to produce non-predictable data. Like a keyboard, mouse and a monitor or videocard. Of course, there’s a lot more to it, but we really don’t need to know this. What we need to know is that there has to be a “bit bucket” of more than 256bytes of entropy for the certificate creation process to succeed. We also need to know that more enterprise-ish servers, like rack- or blade-servers tend to be void of things like directly attached keyboards, mouses and monitors that the linux kernel needs to be able to generate entropy. And herein lies the problem. If you have a new server that is not in full service (likely since we are trying to deploy the monitoring on it) which means that there’s not much random data flowing through the hardware and there’s no keyboard or mouse or monitor connected to it there is quite the risk that the system entropy is going to be very low. Of the linux systems that I have been deploying OpsMgr agents to, about half have failed because of “Not enough entropy”. So, here’s the steps I usually takes to ensure that discovery works. I use PuTTY to connect to the soon-to-be-monitored servers. This guide also assumes that you have SU rights on the system since all of these steps (except #1) needs it.

Check you current entropy
```
cat /proc/sys/kernel/random/entropy_avail
```
Is it less than, or close to, 256? It probably is. If you don’t feel like connecting a mouse and start wiggling it around—not really feasible in a data center—and see if the entropy increases, you can generate your own random data.
Generate you own random data.
Be advised that this forced entropy will not be as random as the system-created on and thus not as secure. How much more insecure it is, I don’t know, and quite frankly I prefer to have my systems monitored yet slightly less secure than not monitored at all. Anyway, you can force your own random data by running:
```
dd if=/dev/urandom of=~/.rnd bs=1 count=1024
```
This creates a .rnd file with 1024B of random data that the certificate creation process will use instead of the system entropy if the file exists.
Uninstall and re-discover
The first failed attempt of discovery will most likely leave a non-working agent installation that we have to remove. Otherwise we will just be stuck with an “Access Denied” error. Run:
```
rpm –e scx
```
Now, try to discover the system again.

Failed again?
Try generating the certificate manually by running:

/opt/microsoft/scx/bin/tools/scxsslconfig -f –v
/opt/microsoft/scx/bin/tools/scxadmin –restart

Retry discovery again.

Still fails?
Uninstall the agent once more as instructed in step 3.

Stese steps have solved my problems 100% on both SUSE and RedHat and hopefully they will help you too.

Interestingely enough, these problems seems to be connected to some changes in the 2.6 kernel and basically everything that uses SSL-ish certificates will be affected. Even though the symptoms may be a bit more subtle, like time-outs and disconnects. For “headless” servers like those I usually to administer where the random data tend to be much lower, there’s even specialised hardware whose sole purpose is to generate random data, like the Entropy Key. I have also been told that new servers is likely to be equipped with entropy chipsets to make sure that there’s chaos enough to avoid these new-found oddities.

Sources:
http://social.technet.microsoft.com/Forums/en-US/crossplatformsles/thread/f94ec905-23ac-4444-b9f8-644fec3ae357

http://www.askrenzo.com/oracle/SCOM/SCOM_discovering_nodes.html

Categories: OpsMgr 2007, SLES | Tags: How-To, Linux, OpsMgr, TroubleShooting, X-Plat

(re)Gain sysadmin access to SQL2005 or SQL2008

Posted on November 19, 2009 by Sam T

2 comments

In SQL Server 2005 and 2008 the local Administrators account is not sysadmin by default. This makes it even more important that the one setting up the Database also remembers to add a SQL Server admins group to the sysamin role. If this step is forgotten, the user installing the database server is the only one that will ever be sysadmin.

In some extreme cases I’ve seen situations where no one except some dude on vacation is sysadmin and there’s a bunch of applications that needs to be installed/upgraded. In these cases I have also been assigned Local Administrator rights on the server, but since the local Administrators group isn’t sysadmin either I still cannot login to the SQL server.
What to do!?

Thanks to Raul Carcia’s blog post it’s not that a big deal. The instructions is written for SQL Server 2005, but works equally fine on SQL Server 2008 and the only requirement is that you are a local server administrator.
Here’s what to do:

Open the SQL Server Configuration Manager.
In SQL Server Services, open the properties for the SQL Server instance you need access to.
In the Advanced tab, locate Startup Parameters.
Add “;-m” to the end of that line.
Press OK and restart the SQL Server into “Maintenance Mode” or “Single User Mode” if you like. (check that a restart is OK first )
Open a command prompt (right-click, “Run as Administrator” in Windows 2008) and go to C:Program FilesMicrosoft SQL Server100ToolsBinn
(C:Program FilesMicrosoft SQL Server90ToolsBinn for SQL2005)
Execute
```
sqlcmd /A /E /S&lt;SERVERINSTANCE&gt;
```
(use . for local default instance and .INSTANCE for local named instance)

In the CLI, execute:

EXEC sp_addsrvrolemember 'DOMAINyourusername', 'sysadmin';
GO

Return to the SQL Server Configuration Manager and restore the Startup Parameters to it’s previous settings.
Restart the SQL Server instance to allow users to access it again.

Now, you should be able to login to the SQL server with sysadmin rights using your current user. This would also be a good point in time to actually establish a SQL Server Admins group (local or domain) to add to the sysadmin role to avoid having others to the above steps when you, yourself, happens to be on vacation.

As Raul Carcia point out in his original post, this is really a disaster recovery procedure and there’s definitely nothing sneaky about it since it leaves quite alot of trails in the event logs.

All in all, a Great article by Raul and all credit should go his way.

Categories: OpsMgr 2007, SQL 2005, SQL 2008 | Tags: How-To, SQL Server, SQL Server 2005, SQL Server 2008

Installing SQL Reporting Services 2005 on Windows 2008 x64

Posted on November 2, 2009 by Sam T

1 comment

Let’s say you have followed this guide: http://support.microsoft.com/kb/938245/

Still not working? The one thing I forgot, or rather did not find in any of the guides, was to change the website application pool to “Classic .NET AppPool”. It is actually noted in KB938245 but only after the installation, during the configuration. For some reason I have not been able to install Reporting Services 2005 on Windows 2008 without changing this prior to the installation.

Maybe I am doing it wrong but this seems to be working all right for me.

Categories: OpsMgr 2007, SQL 2005, SQL 2008 | Tags: How-To, IIS7, Reporting Services, x64

Replace/Change a Gateway Server

Posted on September 24, 2009 by Sam T

1 comment

If you are looking into replacing an (or just switching to another primary) Operations Manager 2007 Gateway Server for any reason, there’s a little more to consider than just right-clicking the clients and selecting “Change Primary Management Server” in the Operations Console.
You could end up with agents not being able to connect to the Management Group at all due to a small problem with the order in which Operations Manager do things.

Here’s basically what happens:

You tell Operations Manager to change Primary Management Server for AGENTX from GW1 to GW2.
The SDK Service (i guess) tells GW1 that “You’re no longer the Primary Management Server for AGENTX”
GW1 acknowledges this and stops talking to AGENTX. And I mean Completely stops talking to AGENTX.
OpsMgr then tells GW2 to start accepting communication from AGENTX.
OpsMgr tries to tell AGENTX that it should talk to GW2 since GW1 won’t listen.

Spotted the problem?
This modus operandi probably works when agents are on the same network and in the same domain where fail-over is sort of automatic. The problem we are facing now is that the server are telling the Gateway to stop accepting communications to and from the agent before the agent is notified that there is a new Gateway server to talk to. The agent will continue to talk to GW1 but will be completely ignored and you will probably start seeing events in the Operations Manager eventlog on GW1 with EventID 20000.

How do I get around this little feature then?

No matter if you found this article after running into the mentioned troubles or if you are googling ahead of time to be prepared, the fix is the same and consists of a few powershell scripts. These scripts are out there allready, but in different contexts, hence this post.

First step: Install the new Gateway

Documentation on this from Microsoft is good enough, but here’s the short version.

Verify name resolution to and from Gateway server and Management Server
Create certificate for the Gateway server
Approve the Gateway server
Install Gateway server
Import certificates on Windows system
Run MOMCertImport.exe on Gateway server to add the certificate into Gateway server configuration
Wait

The wait is for the gateway server to get all needed configuration from RMS and to download all neccesary management packs, run all the discovery scripts and so on. When the Operations Manager event log has calmed down a bit, move to step two.

Second step: Configure Agent Failover

Connect to an Operations Manager Command Shell. Any will do, as long as it’s connected to the correct Management Group.
Then run the following script:

$primaryGW= Get-ManagementServer | where {$_.Name -eq 'GW2.domain.local'}
$failoverGw = Get-ManagementServer | where {$_.Name -eq 'GW1.domain.local'}
$agents = Get-Agent | where {$_.primarymanagementservername -eq 'GW1.domain.local'}
Set-ManagementServer -AgentManagedComputer: $agents -PrimaryManagementServer: $primaryGW -FailoverServer: $failoverGw

Remember to change “GW1.domain.local” to you OLD Gateway servername and “GW2.domain.local” to your NEW Gateway servername.
If you don’t know powershell, this script basically configures all agents using the old Gateway to use the new one as primare, but keep the old one as a fail-over server. The Gateways will still get to know the changes before the agents, but since the old on is still listening to the agents (though, as the fail-over host) it will be able to tell them to go to the new one, GW2.

Categories: OpsMgr 2007, PowerShell | Tags: How-To, OpsMgr, PowerShell, Script

Clearing Disabled Discovery in OpsMgr 2007

Posted on April 20, 2009 by Sam T