bitkeeper revision 1.655 (3fe4ddc5kjuJ5C3c69KvtT7oUuzn4g)

Merge nidd.cl.cam.ac.uk:/auto/groups/xeno/BK/xeno-1.2.bk
into nidd.cl.cam.ac.uk:/auto/anfs/scratch/labyrinth/iap10/xeno-clone/xeno.bk

1 files changed, 138 insertions, 76 deletions

diff --git a/tools/examples/createlinuxdom.py b/tools/examples/createlinuxdom.py
index d01a2ea0b7..e183b422f8 100755
--- a/tools/examples/createlinuxdom.py
+++ b/tools/examples/createlinuxdom.py
@@ -2,107 +2,169 @@
 
 #
 # Example script for creating and building a new Linux guest OS for Xen.
+# It takes an optional parameter that specifies offsets to be added to the
+# ip address and root partition numbers, enabling multiple domains to be
+# started from the one script.
+#
+# Edit as required...
 #
 
-import Xc, XenoUtil, sys, os
+import Xc, XenoUtil, string, sys, os, time, socket
 
-# Variable declaration. Set these up properly later on, as needed.
-nfsserv = nfspath = root_partn = usr_partn = ""
+# initialize a few variables that might come in handy
+thishostname = socket.gethostname()
+guestid = 0
+if sys.argv >= 2:
+    guestid = string.atoi(sys.argv[1])
+    print "Offset to add to guest's IP etc : %d\n" % guestid
+ 
+##### This section of the code establishes various settings to be used 
+##### for this guest virtual machine
 
-# STEP 1. Specify kernel image file.
-image = "FULL_PATH_TO_IMAGE"
+# STEP 1. Specify kernel image file. Can be gzip'ed.
+image = "../../../install/boot/xenolinux.gz"
 
 # STEP 2. How many megabytes of memory for the new domain?
 memory_megabytes = 64
 
 # STEP 3. A handy name for your new domain.
-domain_name = "My new domain"
+domain_name = "This is VM %d" % guestid
+
+# STEP 4. Specify IP address(es), netmask and gateway for the new
+# domain.  You need to configure IP addrs within the domain just as
+# you do normally.  This is just to let Xen know about them so it can
+# route packets appropriately. 
 
-# STEP 4. Specify IP address, netmask and gateway for the new domain.
-ipaddr  = "ADDRESS"
+#ipaddr = ["111.222.333.444","222.333.444.555"]
+ipaddr  = [XenoUtil.add_offset_to_ip(XenoUtil.get_current_ipaddr(),guestid)]
 netmask = XenoUtil.get_current_ipmask()
 gateway = XenoUtil.get_current_ipgw()
+nfsserv = '169.254.1.0'  # You need to set this if you're using NFS root
 
-# STEP 5a. Specify NFS server and path to rootfs (only needed for network boot)
-nfsserv = "ADDRESS"
-nfspath = "FULL_PATH_TO_ROOT_DIR"
-
-# STEP 5b. Specify root partition on local disc (if not NFS booting)
-#root_partn = "/dev/sda2"
-# (NB. The following is only needed for a separate shared read-only /usr)
-# (usr_partn  = "/dev/sda6")
-
-# STEP 6. Check that the following cmdline setup is to your taste.
-cmdline = "ip="+ipaddr+":"+nfsserv+":"+gateway+":"+netmask+"::eth0:off"
-if root_partn:
-    # Boot from local disc. May specify a separate /usr.
-    cmdline = cmdline + " root="+root_partn+" ro"
-    if usr_partn:
-        " usr="+usr_partn
-elif nfsserv:
-    # NFS boot
-    cmdline = cmdline + " root=/dev/nfs"
-    cmdline = cmdline + " nfsroot="+nfspath
-
-if root_partn:
-    root_info = XenoUtil.lookup_blkdev_partn_info(root_partn)
-    if not root_info:
-        print "Could not obtain info on partition '" + root_partn + "'"
-        sys.exit()
+# STEP 5. Identify any physcial partitions or virtual disks you want the
+# domain to have access to, and what you want them accessible as
+# e.g. vbds = [ ('phy:sda1','sda1', 'w'),
+#	 ('phy:sda4','sda%d' % (3+guestid), 'r'), 
+#	 ('vd:as73gd784dh','hda1','w') ]
 
-if usr_partn:
-    usr_info = XenoUtil.lookup_blkdev_partn_info(usr_partn)
-    if not usr_info:
-        print "Could not obtain info on partition '" + usr_partn + "'"
-        sys.exit()
+vbds = [ ('phy:sda%d'%(7+guestid),'sda1','w' ), 
+	 ('phy:sda6','sda6','r'),
+	 ('phy:cdrom','hdd','r') ]
 
-if not os.path.isfile( image ):
-    print "Image file '" + image + "' does not exist"
-    sys.exit()
+# STEP 6. Build the command line for the new domain. Edit as req'd.
+# You only need the ip= line if you're NFS booting or the root file system
+# doesn't set it later e.g. in ifcfg-eth0 or via DHCP
+# You can use 'extrabit' to set the runlevel and custom environment
+# variables used by custom rc scripts (e.g. DOMID=, usr= )
 
-xc = Xc.new()
+ipbit = "ip="+ipaddr[0]+":"+nfsserv+":"+gateway+":"+netmask+"::eth0:off"
+rootbit = "root=/dev/sda1 ro"
+#rootbit = "root=/dev/nfs nfsroot=/full/path/to/root/directory"
+extrabit = "4 DOMID=%d usr=/dev/sda6" % guestid 
+cmdline = ipbit +" "+ rootbit +" "+ extrabit
 
-id = xc.domain_create( mem_kb=memory_megabytes*1024, name=domain_name )
-if id <= 0:
-    print "Error creating domain"
-    sys.exit()
+# STEP 7. Set according to whether you want the script to watch the domain 
+# and auto-restart it should it die or exit.
 
-if xc.linux_build( dom=id, image=image, cmdline=cmdline ):
-    print "Error building Linux guest OS"
-    xc.domain_destroy ( dom=id )
-    sys.exit()
+auto_restart = False
+#auto_restart = True
 
-if root_partn:
-    if xc.vbd_create( dom=id, vbd=root_info[0], writeable=1 ):
-        print "Error creating root VBD"
-        xc.domain_destroy ( dom=id )
+
+##### Print some debug info just incase things don't work out...
+##### 
+
+print "Domain image          : ", image
+print "Domain memory         : ", memory_megabytes
+print "Domain IP address(es) : ", ipaddr 
+print "Domain block devices  : ", vbds
+print 'Domain cmdline        : "%s"' % cmdline
+
+
+##### Code beyond this point is actually used to manage the mechanics of
+##### starting (and watching if necessary) guest virtual machines.
+
+# Obtain an instance of the Xen control interface
+xc = Xc.new()
+
+# This function creates, builds and starts a domain, using the values
+# in the global variables, set above.  It is used in the subsequent
+# code for starting the new domain and rebooting it if appropriate.
+def make_domain():
+    """Create, build and start a domain.
+    Returns: [int] the ID of the new domain.
+    """
+
+    # set up access to the global variables declared above
+    global image, memory_megabytes, domain_name, ipaddr, netmask
+    global vbds, cmdline, xc
+    	
+    if not os.path.isfile( image ):
+        print "Image file '" + image + "' does not exist"
         sys.exit()
-    if xc.vbd_grow( dom=id,
-                    vbd=root_info[0],
-                    device=root_info[1],
-                    start_sector=root_info[2],
-                    nr_sectors=root_info[3] ):
-        print "Error populating root VBD"
-        xc.domain_destroy ( dom=id )
+
+    id = xc.domain_create( mem_kb=memory_megabytes*1024, name=domain_name )
+    print "Created new domain with id = " + str(id)
+    if id <= 0:
+        print "Error creating domain"
         sys.exit()
 
-if usr_partn:
-    if xc.vbd_create( dom=id, vbd=usr_info[0], writeable=0 ):
-        print "Error creating usr VBD"
+    ret = xc.linux_build( dom=id, image=image, cmdline=cmdline )
+    if ret < 0:
+        print "Error building Linux guest OS: "
+        print "Return code from linux_build = " + str(ret)
         xc.domain_destroy ( dom=id )
         sys.exit()
-    if xc.vbd_grow( dom=id,
-                    vbd=usr_info[0],
-                    device=usr_info[1],
-                    start_sector=usr_info[2],
-                    nr_sectors=usr_info[3] ):
-        print "Error populating usr VBD"
+
+    # setup the virtual block devices
+    for ( uname, virt_name, rw ) in vbds:
+	virt_dev = XenoUtil.blkdev_name_to_number( virt_name )
+
+	segments = XenoUtil.lookup_disk_uname( uname )
+	if not segments:
+	    print "Error looking up %s\n" % uname
+	    xc.domain_destroy ( dom=id )
+	    sys.exit()
+
+	if xc.vbd_create( dom=id, vbd=virt_dev, writeable= rw=='w' ):
+	    print "Error creating VBD vbd=%d writeable=%d\n" % (virt_dev,rw)
+	    xc.domain_destroy ( dom=id )
+	    sys.exit()
+
+	for (s_dev,s_start,s_len,s_type) in segments:
+	    if xc.vbd_grow( dom=id,
+			    vbd=virt_dev,
+			    device=s_dev,
+			    start_sector=s_start,
+			    nr_sectors=s_len ):
+		print "Error populating VBD vbd=%d\n" % virt_dev
+		xc.domain_destroy ( dom=id )
+		sys.exit()
+
+    # setup virtual firewall rules for all aliases
+    for ip in ipaddr:
+	XenoUtil.setup_vfr_rules_for_vif( id, 0, ip )
+
+    if xc.domain_start( dom=id ) < 0:
+        print "Error starting domain"
         xc.domain_destroy ( dom=id )
         sys.exit()
 
-XenoUtil.setup_vfr_rules_for_vif( id, 0, ipaddr )
+    return id
+# end of make_domain()
+
+
+
+# The starting / monitoring of the domain actually happens here...
+
+# start the domain and record its ID number
+current_id = make_domain()
+
+# if the auto_restart flag is set then keep polling to see if the domain is
+# alive - restart if it is not by calling make_domain() again (it's necessary
+# to update the id variable, since the new domain may have a new ID)
 
-if xc.domain_start( dom=id ):
-    print "Error starting domain"
-    xc.domain_destroy ( dom=id )
-    sys.exit()
+while auto_restart:
+    time.sleep(1)
+    if not xc.domain_getinfo(current_id):
+        print "The virtual machine has terminated, restarting in a new domain"
+        current_id = make_domain()