A "creative fix" (aka, ugly hack) for saving images on dongle-booted nodes.

os/create-image

 #!/usr/bin/perl -wT
 
 #
-# Copyright (c) 2000-2011 University of Utah and the Flux Group.
+# Copyright (c) 2000-2012 University of Utah and the Flux Group.
 # 
 # {{{EMULAB-LICENSE
 # 
@@ -149,6 +149,19 @@ if ($^O eq 'linux') {
 	$dunit -= 4 if ($dtype eq 'ad' && $dunit > 3);
 	$dunit =~ y/01234567/abcdefgh/;
 
+	#
+	# XXX woeful TPM dongle-boot hack.
+	# If we are imaging /dev/sda and dmesg reports that
+	# that device is write-protected, assume it is the boot dongle
+	# and use /dev/sdb instead!
+	#
+	if ($dunit eq "a") {
+	    if (!system("dmesg | fgrep -q '[sda] Write Protect is on'")) {
+		print STDERR "WARNING: suspect dongle-booted node, using sdb instead of sda\n";
+		$dunit = "b";
+	    }
+	}
+
 	$device = "/dev/sd$dunit";
 }