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Lots of people regularly use the Microsoft iSCSI Software Initiator on physical machines to attach iSCSI LUNs from filers to hosts. This is an add on free download for Server 2003, and comes pre-installed on Server 2008.

 In general, on physical machines, it works fine.

So assuming that it’d work just fine on a virtual machine, we tried to use it on some production machines running Small Business Server 2003.  It seems to load just fine, and works like it usually does on a “real” machine – *BUT* it has terrible throughput under load.  It’ll even disconnect at random times.  Uninstalling/reinstalling, and lots of fiddling around didn’t help.

Of course, we went to Google to see if others have issues with it, and there’s *LOTS* of whining about this, both on VMware ESX and XenServer.

It’s possible that it has been addressed in Server 2008.  We saw this on 2003, and haven’t attempted to replicate the issue on 2008 vm’s.

Nonetheless, we suggest you figure out another way to attach iSCSI LUNs from a filer to a Windows virtual machine.  Both ESX and XenServer allow you to easily present iSCSI based disks to vm’s inside their virtualization environments.  Don’t do it with the Microsoft iSCSI Software Initiator from within the guest.

I took 070-647 Windows Server 2008, Enterprise Administrator exam again today.  I didn’t pass again.  I got the exact same score, 653 out of 700.  Like I said in my previous post on 070-647, these MCITP:EA exams are some of the hardest exams I’ve ever taken.  I’ve taken a lot, from a lot of different vendors.

NexentaStor 3.0 Main Dashboard

I’ve been using Openfiler for a long time now, but I’m always open to alternatives.  Recently I stumbled across NexentaStor, which is a software product you can load on your servers to make them into filers, like Openfiler.  NexentaStor is available both in an Community Edition, as well as a relatively inexpensive Enterprise Edition, which comes with all the bells and whistles like built in block level replication. Read more

“The only reason for time is so that everything doesn’t happen at once.”

At work, I have an integrated authentication system based on Windows Active Directory.  All clients, Linux, Unix, and Windows, use Active Directory for user names and passwords.  Active Directory is actually a good implementation of Kerberos.  It does pretty good LDAP as well.  I used some of Scott Lowe’s interoperability blog recipes to get this to work, namely this post for Linux, and this one for Solaris.

One requirement for a reliable Kerberos service is that every clock on every participating machine has to be synchronized.  By default Windows domain controllers act as Network Time Protocol (NTP) servers, and Windows clients know to sync with them.  We configure our Linux and Unix machines to use them as well.

There’s some issues with using Windows domain controllers as NTP servers…

Read more

My GNU Truck

I got a new GNU truck during the Cash for Clunkers bonanza.  (GNU is one of the main organizations that built the tools we call Linux.)  It’s a 2009 Toyota Tacoma Prerunner.  It’s the first new car I’ve ever had, and I really like it. Read more