Pfsense installation not possible after using geom mirror option

[purple_dragon]

I tested pfsense on a sever with two harddisk and installed it successfully on one of them.
After some tests I saved the pfsense configuration and was doing a reinstall trying to install it on the geom softraid.
So I created geom mirror using the installer and tried to install pfsense on the newly created mirror.
But the installer always crashes at about 35%.
Now when I reboot the pfsensemirror is still shown additional to the two harddisks and I cannot delete it with the install wizard.
But I cannot install on the harddisk either now as the installer crashes no matter on which of the two harddisks I try to install.
So at the moment I'm stuck. I deleted the partitions cleaned the mbr on both disks, but the pfsensemirror is still shown when I start the pfsense installer.
I can also not use the live cd boot to get to the command shell as the live cd boot is stuck configuring the WAN interface waiting for a dhcp server and I do not have one in my network.
So what can I do to delete the  pfsense gmirror. Using a freebsd ISO file and boot from this to delete the mirror?
Which other options do I have?
I want to delete the mirror , install pfsense on one of the two disks like I did on my fiirst install and create the mirror then again using the shell and not theinstaller.

Thanks for your help in advance

[JoelC707]

Deleting the partition(s) won't break the mirror, neither will clearing the MBR. I've never experimented with a mirror in pfsense setup as I've always relied on raid controllers for that. My suggestion since you can't seem to get back into setup is to grab UBCD. You can burn it to a disc or USB stick and boot parted magic. I've used this to clear out many "stuck" configs on drives that OS installers wouldn't clear out. Not sure how FreeBSD differs but you may even be able to use parted magic to make your mirror first and then just direct pfsense to that existing mirror but I'll let others chime in on that.

Joel

[jimp]

Boot the pfSense CD, then wipe the drives completely from the shell.

dd if=/dev/zero of=/dev/ad0 BS=1M
dd if=/dev/zero of=/dev/ad1 BS=1M

Substitute the actual drive devices for ad0/ad1 (e.g. if they are SATA they could be ad4/ad6, etc), do "ls -l /dev/ad*" to see the drives if they are ATA/SATA, /dev/da* if they are SCSI