Category : Microsoft

Creating an NFS share on Windows XP

Recently, on the Mythtv-users mailing list, Gabe Rubin posted a question asking why he was getting no thumbnails in his mythweb view. Having already resolved that problem in my own environment, I told him that there was a bug in CIFS that showed up when using the MythTV uPnP code (which Mythweb does as of 0.21) and he was better off using NFS if possible. I also offered to help him get NFS working using Microsoft Services for Unix (SFU). Silly me 🙂

I’d never previously setup SFU under Windows XP. I’d only ever used it under a ‘Server’ version of Windows. As it turns out, there is a bug (or is that a feature?) in the User Name Mapping (UNM) feature of SFU that causes it to fail on Windows XP if the username/password combination of the *nix account you want to map does not match the username/password combination of the Windows account it is mapped to. The way UNM is supposed to work, is that it will take any *nix user account and map it to any Windows user account. Username and password is not supposed to matter, and indeed, this is the way it works in Windows Server. Not so for Windows XP though.

 So, for anybody out there trying to get SFU working properly (the NFS Server portion in particular) on a Windows XP machine, here are step-by-step instructions for what worked for me in my test-lab… Read More

Installing Linux with a GUI under MS Virtual PC

Since I haven’t been able to find a version of VMWare Server that works properly under Vista as a host system, I have fallen back to using MS Virtual PC 2007 to run the VMs on my desktop machine. This works well enough for the windows VMs, but installing linux can be frustrating. The X-Windows installer always seems to want to come up in 24 bit colour mode, but Virtual PC thinks it’s 16 bit colour mode. This results in a corrupt display and the failure to continue the installation. To work around this, you need to remember to tell the linux installer to run in either text mode or vesa compatibility mode.

Use text mode if you won’t be installing X-Windows…

boot: linux text

Use vesa compatibility mode if you want the full GUI experience…

boot: linux vesa

I’ve tried this with various Fedora/Centos releases, but it should work with whatever your favorite flavour of linux is.

VMWare Guest clocks running too fast

I use VMWare Server on a couple of machines to run various linux and windows guest virtual machines. Depending on what cpu and what kind of power management I have enabled on the host machine I can see some very severe clock drift on the guests. To work around the clock drift I usually need to add a few items to the vmware hosts global config file.

For linux hosts, the config file can usually be found at…

/etc/vmware/config

For windows hosts, the config file location is…

C:\Documents and Settings\All Users\Application Data\VMware\VMware Server\config.ini

Open the global config file and add the following lines then restart the vmware server service/daemon…

host.cpukHz = 2000000
hostinfo.noTSC = TRUE
tools.syncTime = TRUE

The first line tells vmware what the maximum clock frequency of the host cpu is (2GHz in my example). The ‘hostinfo.noTSC’ line informs VMWare that the cpu is not running at a constant clock rate (speedstep or cpufreq or power management is active) and the timestamp counter can’t be trusted so use it as little as possible. The last line sets the default to use vmware-tools timesync function. The addition of these items is usually enough to keep the guest clocks running close enough to proper time that ntp will stay locked.

Automatic Updates acting up again…

Once more I find that one of my Windows 2000 boxen has decided it no longer likes Windows Update Service and is spewing the following error into the application eventlog every 10 minutes.

Event Source: ESENT
Event ID: 427
Description: wuaueng.dll (1588) The database engine could not access the file called C:\WINNT\SoftwareDistribution\DataStore\Logs\edb.log.

The fix is pretty straight forward. Simply stop the ‘Automatic Update’ service on the affected machine, delete the %windir%\SoftwareDistribution\DataStore\Logs\edb.log file, then restart the service. The log file will be recreated the next time Automatic Updates checks in with the WSUS server and the eventlog error will be gone.