xen October 2007

xen@lists.fedoraproject.org

32 participants
33 discussions

How is network bridging for Xen handled in F7?
by Christian Reiter 06 Feb '08

06 Feb '08

Hi! Can anybody tell me where i can find docs about handling network bridges for xen domUs in Fedora 7? Something changed since FC6, so i cannot figure out how to create simple bridges without dhcp for my xen domUs. All what i want is: xenbrINTERNET should bridge to eth1 xenbrLAN should bridge to eth0 eth0 and eth1 of my dom0 should also have an IP Address. I do not want routing or nat for my domUs. Thanks! regards, christian

3 7

Guest VM dropping connection.
by Ubaidul Khan 15 Jan '08

15 Jan '08

I am running RHEL5 Guest and Host. The guest OS is dropping network connections occasionally(I noticed my ssh session suddenly terminated). The guest is configured with private network interface and a public network interface. Following are the bridge/network settings for the host: bridge name bridge id STP enabled interfaces xenbr0 8000.feffffffffff no vif2.0 vif1.0 peth0 vif0.0 xenbr1 8000.fefffffffffe no vif2.1 peth1 vif0.3 xenbr1 is dedicated to provide the private network link for the guest os. Following is the guest OS configuration: # Automatically generated xen config file name = "saleen_webvm0" memory = "1000" disk = [ 'tap:aio:/vms/img/redhat/linux/es/5.0/x86_64/saleen_webvm0.img,xvda,w','phy:/dev/sdc,xvdb,w' ] vif = [ 'mac=00:16:3e:2e:6f:e1, bridge=xenbr0','mac=00:16:3e:2f:9e:b1, bridge=xenbr1',] # vif = [ 'mac=00:16:3e:2e:6f:e1, bridge=xenbr0',] vfb = ["type=vnc,vncunused=1"] uuid = "122374dc-26a3-cb0d-99f8-3393e2481777" bootloader="/usr/bin/pygrub" vcpus=2 on_reboot = 'restart' on_crash = 'restart' Following is the output of ifconfig: eth0 Link encap:Ethernet HWaddr 00:14:4F:40:D8:70 inet addr:xxx.xxx.xxx.xxx Bcast:xxx.xxx.xxx.255 Mask:255.255.255.0 inet6 addr: fe80::214:4fff:fe40:d870/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:79313 errors:0 dropped:0 overruns:0 frame:0 TX packets:1167 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:6619719 (6.3 MiB) TX bytes:115448 (112.7 KiB) eth1 Link encap:Ethernet HWaddr 00:14:4F:40:D8:71 inet addr:xxx.xxx.xxx.xxx Bcast:xxx.xxx.xxx.255 Mask:255.255.255.0 inet6 addr: fe80::214:4fff:fe40:d871/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:12 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:720 (720.0 b) peth0 Link encap:Ethernet HWaddr FE:FF:FF:FF:FF:FF inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link UP BROADCAST RUNNING NOARP MTU:1500 Metric:1 RX packets:105404 errors:0 dropped:0 overruns:0 frame:0 TX packets:13455 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:9122426 (8.6 MiB) TX bytes:1997833 (1.9 MiB) Base address:0x8c00 Memory:fa5e0000-fa600000 peth1 Link encap:Ethernet HWaddr FE:FF:FF:FF:FF:FE inet6 addr: fe80::fcff:ffff:feff:fffe/64 Scope:Link UP BROADCAST RUNNING NOARP MTU:1500 Metric:1 RX packets:9239102 errors:0 dropped:0 overruns:0 frame:0 TX packets:5337342 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:12420212276 (11.5 GiB) TX bytes:523849820 (499.5 MiB) Base address:0x8800 Memory:fa5c0000-fa5e0000 vif1.0 Link encap:Ethernet HWaddr FE:FF:FF:FF:FF:FF inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link UP BROADCAST RUNNING NOARP MTU:1500 Metric:1 RX packets:2174 errors:0 dropped:0 overruns:0 frame:0 TX packets:80032 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:32 RX bytes:446031 (435.5 KiB) TX bytes:6941997 (6.6 MiB) vif2.0 Link encap:Ethernet HWaddr FE:FF:FF:FF:FF:FF inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link UP BROADCAST RUNNING NOARP MTU:1500 Metric:1 RX packets:10084 errors:0 dropped:0 overruns:0 frame:0 TX packets:89284 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:32 RX bytes:1186096 (1.1 MiB) TX bytes:7380350 (7.0 MiB) vif2.1 Link encap:Ethernet HWaddr FE:FF:FF:FF:FF:FF inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link UP BROADCAST RUNNING NOARP MTU:1500 Metric:1 RX packets:5337343 errors:0 dropped:0 overruns:0 frame:0 TX packets:9239082 errors:0 dropped:20 overruns:0 carrier:0 collisions:0 txqueuelen:32 RX bytes:403712612 (385.0 MiB) TX bytes:12383227754 (11.5 GiB) Any help is greately appreciated. _________________________________________________________________ http://liveearth.msn.com

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RHEL4 DomU Update Problem
by Jim Klein 02 Nov '07

02 Nov '07

Am attempting to update a RHEL4 domU from a custom created Xen kernel (created before RHEL5) to a supported kernel (2.6.9-55.0.9.ELxenU) and RHEL5 host without success. For some reason, the kernel can no longer find xvda. Boots fine on the old kernel and host, so I'm at a bit of a loss. Host has other domUs booted off the same SAN, with no security restrictions, so I don't see how it could be hardware. Copy of configs and partial debug log below. Ideas? Conf: name = "do5" memory = "1024" disk = [ 'phy:/dev/mpath/msa-mpathv0p1,xvda,w', ] vif = [ 'mac=00:16:3e:55:a5:65, bridge=xenbr2' ] vfb = ["type=vnc,vncunused=1"] bootloader="/usr/bin/pygrub" vcpus=1 Grub: root (hd0,0) kernel /vmlinuz-2.6.9-55.0.9.ELxenU ro root=/dev/xvda2 rhgb quiet initrd /initrd-2.6.9-55.0.9.ELxenU.img Debug: [2007-10-30 12:41:21 xend.XendDomainInfo 4121] DEBUG (XendDomainInfo:190) XendDomainInfo.create(['vm', ['name', 'do5'], ['memory', '1024'], ['vcpus', 1], ['bootloader', '/usr/bin/pygrub'], ['image', ['linux', ['ramdisk', '/var/lib/xen/initrd.MpxKQP'], ['kernel', '/var/lib/xen/vmlinuz.6u2e9w'], ['args', 'ro root=/dev/xvda2 rhgb quiet']]], ['device', ['vbd', ['uname', 'phy:/dev/mpath/msa-mpathv0p1'], ['dev', 'xvda'], ['mode', 'w']]], ['device', ['vif', ['bridge', 'xenbr2'], ['mac', '00:16:3e:55:a5:65']]], ['device', ['vkbd']], ['device', ['vfb', ['vncunused', '1'], ['type', 'vnc'], ['display', 'localhost:10.0'], ['xauthority', '/root/.Xauthority']]]]) [2007-10-30 12:41:21 xend.XendDomainInfo 4121] DEBUG (XendDomainInfo:296) parseConfig: config is ['vm', ['name', 'do5'], ['memory', '1024'], ['vcpus', 1], ['bootloader', '/usr/bin/pygrub'], ['image', ['linux', ['ramdisk', '/var/lib/xen/initrd.MpxKQP'], ['kernel', '/var/lib/xen/vmlinuz.6u2e9w'], ['args', 'ro root=/dev/xvda2 rhgb quiet']]], ['device', ['vbd', ['uname', 'phy:/dev/mpath/msa-mpathv0p1'], ['dev', 'xvda'], ['mode', 'w']]], ['device', ['vif', ['bridge', 'xenbr2'], ['mac', '00:16:3e:55:a5:65']]], ['device', ['vkbd']], ['device', ['vfb', ['vncunused', '1'], ['type', 'vnc'], ['display', 'localhost:10.0'], ['xauthority', '/root/.Xauthority']]]] [2007-10-30 12:41:21 xend.XendDomainInfo 4121] DEBUG (XendDomainInfo:397) parseConfig: result is {'shadow_memory': None, 'start_time': None, 'uuid': None, 'on_crash': None, 'on_reboot': None, 'localtime': None, 'image': ['linux', ['ramdisk', '/var/lib/xen/initrd.MpxKQP'], ['kernel', '/var/lib/xen/vmlinuz.6u2e9w'], ['args', 'ro root=/dev/xvda2 rhgb quiet']], 'on_poweroff': None, 'bootloader_args': None, 'cpus': None, 'name': 'do5', 'backend': [], 'vcpus': 1, 'cpu_weight': None, 'features': None, 'vcpu_avail': None, 'memory': 1024, 'device': [('vbd', ['vbd', ['uname', 'phy:/dev/mpath/msa-mpathv0p1'], ['dev', 'xvda'], ['mode', 'w']]), ('vif', ['vif', ['bridge', 'xenbr2'], ['mac', '00:16:3e:55:a5:65']]), ('vkbd', ['vkbd']), ('vfb', ['vfb', ['vncunused', '1'], ['type', 'vnc'], ['display', 'localhost:10.0'], ['xauthority', '/root/.Xauthority']])], 'bootloader': '/usr/bin/pygrub', 'cpu': None, 'maxmem': None} [2007-10-30 12:41:21 xend.XendDomainInfo 4121] DEBUG (XendDomainInfo:1264) XendDomainInfo.construct: None [2007-10-30 12:41:21 xend.XendDomainInfo 4121] DEBUG (XendDomainInfo:1296) XendDomainInfo.initDomain: 9 1.0 [2007-10-30 12:41:21 xend 4121] DEBUG (balloon:127) Balloon: 1049112 KiB free; need 1048576; done. [2007-10-30 12:41:21 xend 4121] INFO (image:136) buildDomain os=linux dom=9 vcpus=1 [2007-10-30 12:41:21 xend 4121] DEBUG (image:199) dom = 9 [2007-10-30 12:41:21 xend 4121] DEBUG (image:200) image = /var/lib/xen/vmlinuz.6u2e9w [2007-10-30 12:41:21 xend 4121] DEBUG (image:201) store_evtchn = 1 [2007-10-30 12:41:21 xend 4121] DEBUG (image:202) console_evtchn = 2 [2007-10-30 12:41:21 xend 4121] DEBUG (image:203) cmdline = ro root=/dev/xvda2 rhgb quiet [2007-10-30 12:41:21 xend 4121] DEBUG (image:204) ramdisk = /var/lib/xen/initrd.MpxKQP [2007-10-30 12:41:21 xend 4121] DEBUG (image:205) vcpus = 1 [2007-10-30 12:41:21 xend 4121] DEBUG (image:206) features = [2007-10-30 12:41:21 xend 4121] DEBUG (blkif:24) exception looking up device number for xvda: [Errno 2] No such file or directory: '/dev/xvda'

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Auto starting domains on boot with Fedora 7 dom0
by Mike W. Harris 31 Oct '07

31 Oct '07

Hi, I have a Fedora 7 dom0 with a few domUs. I'd like to have some of them start when the physical machine reboots. This should be simple, I just put the config file in the /etc/xen/auto directory. Unfortunately we're using libvirt and virt-manager, so we don't have config files. virsh hasn't implemented auto start for xen machines, either. This seems like a pretty common thing to do, has anyone else had any luck? - Mike Harris - Systems University Library - UC Davis

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Error: (9, 'Bad file descriptor')
by Anand Gupta 31 Oct '07

31 Oct '07

Dom0 = centos 5 (32bit), 4GB Ram DomU = centos 5 (PV) (32bit) xen 3.1.2 rc1, compiled using XEN_TARGET_X86_PAE=Y kernel 2.6.18, modified to load areca card drivers initrd image created using the following command mkinitrd -v -f --with=aacraid --with=arcmsr --with=sd_mod --with=scsi_mod initrd-2.6.18-xen.img 2.6.18-xen When i issue xm create for a domU which was working earlier i get the following error xm create ldap Using config file "./ldap". Error: (9, 'Bad file descriptor') Log snippet when the error appears [2007-11-01 01:01:09 4605] ERROR (xmlrpclib2:178) Internal error handling xend.domain.create Traceback (most recent call last): File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/util/xmlrpclib2.py", line 131, in _marshaled_dispatch response = self._dispatch(method, params) File "/usr/lib/python2.4/SimpleXMLRPCServer.py", line 406, in _dispatch return func(*params) File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/server/XMLRPCServer.py", line 72, in domain_create info = XendDomain.instance().domain_create(config) File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/XendDomain.py", line 918, in domain_create self._refresh() File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/XendDomain.py", line 402, in _refresh self.domains[domid].update(dom, refresh_shutdown) File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/XendDomainInfo.py", line 2198, in update self._update_consoles() File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/XendDomainInfo.py", line 792, in _update_consoles self.console_port = self.readDom('console/port') File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/XendDomainInfo.py", line 845, in readDom return xstransact.Read(self.dompath, *args) File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/xenstore/xstransact.py", line 298, in Read return complete(path, lambda t: t.read(*args)) File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/xenstore/xstransact.py", line 352, in complete t = xstransact(path) File "/home/xen/xen-3.1-testing.hg/dist/install/usr/lib/python/xen/xend/xenstore/xstransact.py", line 21, in __init__ self.transaction = xshandle().transaction_start() Error: (9, 'Bad file descriptor') Config file kernel = "/boot/vmlinuz-2.6.18-xen" ramdisk = "/boot/initrd-2.6.18-xen.img" name = "ldap" memory = "1024" disk = [ 'phy:/dev/VolGroup00/ldap,sda1,w'] root = "/dev/sda1 ro" vif = [ 'mac=00:16:3e:12:34:a8, bridge=xenbr0', ] uuid = "bee5f62b-7193-a454-e37e-a151a5be8f45" vcpus=7 The above domU was booting up properly so i am guessing its an issue with the way i have setup xen. -- regards, Anand Gupta

1 3

ARP failing when I ping from host to guest
by kewlemer 27 Oct '07

27 Oct '07

I'm running x86_64 Fedora7 host and 32 bit Fedora 7 guest on KVM. Here what the default bridged network setting gave me - HOST - [root@fed-amd64 ~]# ifconfig eth0 Link encap:Ethernet HWaddr 00:1A:A0:56:52:E5 inet addr:192.168.1.9 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::21a:a0ff:fe56:52e5/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1492 Metric:1 RX packets:4144 errors:0 dropped:0 overruns:0 frame:0 TX packets:4490 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3143529 (2.9 MiB) TX bytes:1026716 (1002.6 KiB) Interrupt:23 Base address:0x6000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:11074 errors:0 dropped:0 overruns:0 frame:0 TX packets:11074 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:49074613 (46.8 MiB) TX bytes:49074613 (46.8 MiB) virbr0 Link encap:Ethernet HWaddr 00:FF:EE:14:6D:91 inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0 inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:61 errors:0 dropped:0 overruns:0 frame:0 TX packets:86 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:9261 (9.0 KiB) TX bytes:12220 (11.9 KiB) vnet0 Link encap:Ethernet HWaddr 00:FF:EE:14:6D:91 inet6 addr: fe80::2ff:eeff:fe14:6d91/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:61 errors:0 dropped:0 overruns:0 frame:0 TX packets:61 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:500 RX bytes:10115 (9.8 KiB) TX bytes:7195 (7.0 KiB) [root@fed-amd64 ~]# Here is what the GUEST landed up with when using the default configuration- [root@fed-guest ~]# ifconfig eth0 Link encap:Ethernet HWaddr 00:16:3E:6B:C6:36 inet addr:192.168.122.195 Bcast:192.168.122.255 Mask:255.255.255.0 inet6 addr: fe80::216:3eff:fe6b:c636/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1492 Metric:1 RX packets:4144 errors:0 dropped:0 overruns:0 frame:0 TX packets:4490 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3143529 (2.9 MiB) TX bytes:1026716 (1002.6 KiB) Interrupt:23 Base address:0x6000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:11074 errors:0 dropped:0 overruns:0 frame:0 TX packets:11074 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:49074613 (46.8 MiB) TX bytes:49074613 (46.8 MiB) virbr0 Link encap:Ethernet HWaddr 00:00:00:00:00:00 inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0 inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:61 errors:0 dropped:0 overruns:0 frame:0 TX packets:86 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:9261 (9.0 KiB) TX bytes:12220 (11.9 KiB) [root@fed-guest ~]# The problem is that I'm unable to ping from the host to the guest (to 192.168.122.195). tcpdump shows that guest is not responding to ARPs for 192.168.122.195. Can anyone tell me why? When I ping from the guest to to 192.168.122.1 and 192.168.122.195, both go through. But when I ssh into either of them to make sure I'm reaching the host, the ssh lands into the guest itself. This means the ping response on the guest is from itself - so the guest is also unable to reach the host. I googled and looked at the following sitew, but they were of not much help for this problem - http://www.gnome.org/~markmc/virtual-networking.html http://watzmann.net/blog/index.php/2007/04/27/networking_with_kvm_and_libvi… Am I missing something ? Thanks, KM

1 1

64-Bit RAM Detection >4GB?
by Dustin Henning 26 Oct '07

26 Oct '07

I have a Core 2 Quad with 8 GiB of RAM. When I installed FC7 (2.6.22.9-91.fc7), it only detected 4GiB (BIOS detects 8GiB). I added mem=8G to the kernel line in grub.conf, and then Gnome System Monitor showed 7.1GiB (vs I think 4.0). I then changed that to mem=16G, and the Gnome System Monitor shows 7.8 GiB. /proc/meminfo MemTotal shows 8201832kB, so that seems about right. That said, the problem seems to be solved for the kernel mentioned above. However, and this is why I am submitting this to the fedora-xen mailing list, the virtualization kernel (2.6.20-2936.fc7xen) shows 3.1GiB in Gnome System Monitor and 3214456KB in /proc/meminfo MemTotal. Additionally, "xm info" shows 3327 for total memory, so the problem isn't that it is there but not assigned to dom0. I tried the same thing with grub.conf for xen, but it did not work, mem=8G and mem=16G had no effect (this is shown to be a valid parameter in the Xen manual at [http://tx.downloads.xensource.com/downloads/docs/user/#SECTION0413000000000 0000000]). Since it didn't work on the kernel line, I tried it on the module (vmlinuz) line that has the other FC grub arguments, and that did not work either; then I tried placing that on both lines (also to no avail). I also tried dom0_mem=8G on the kernel line, and that caused a kernel panic stating not enough physical memory (got the same thing with dom0_mem=4G). Finally, as a side note, /proc/meminfo VmallocTotal shows 34359738367kB regardless of all of the above, and I don't know if that is normal or not (swap partition is 2GiB). Please let me know if you have fedora 7 x86_64 xen working with >4GB of memory, if there is any additional information that might be helpful, or if you have any suggestions I might try in order to resolve this. Thank you, Dustin

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Re: [Fedora-xen] Re: problem creating my 1st VM
by Guillaume 26 Oct '07

26 Oct '07

> In the e-mail I just sent, I showed an example for using initrd. > Try that. Sorry, but I just get your message after I mine :) I try your tips, and it seems to work... The initrd image is loaded and... I have a new error message. I'll investigate on it asap, but for this week its over :) >However, the virtual hda should not be detected as a generic scsi > device, it should be detected as a generic ide device. A virtual sda might > be detected as a scsi device, but I don't know if you can even do that in a > paravirtualized environment (I think you can in an HVM, but the virtual BIOS > won't boot to a scsi device in that situation). I'll try the "hda option" next time. For information about my xdi file, i create it with dd, mount it as a loop device, format it with ext3 FS and after copy my "/" on it. I choose use xdi extension on my own, but its stand for "Xen Disk Image". Its not related with any other ext. Bye :) -- Guillaume

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problem creating my 1st VM
by Guillaume 26 Oct '07

26 Oct '07

Hi list, I' trying to create my first vm with Xen, and I experience some problems. I follow some How to's and xen docs to build my own config file, but maybe, there are some errors inside it. I have the following problem, after i start my guest domain, the kernel boot & then a kernel panix is displayed : VFS: Cannot open root device "hda1" or unknown-block(0,0) Please append a correct "root=" boot option Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) I try to start this Virtual machine from vmware workstation where i install Xen (Dom0 work perfectly). My config is make up of these lines : kernel = "/boot/vmlinuz-2.6.20-2936.fc7xen" root = "/dev/hda1 ro" name = "test_Linux" cdrom = "/dev/cdrom" memory = "128" builder = "linux" name = "linux" disk = [ "file:/xenroot/linux/linux.xdi,hda1,w" ] Additionnals questions : a) Does i must use a modified Xen linux kernel, or, can I use a "normal/standard" kernel to boot up my VM? b) Is it possible to start a fresh install of Fedora directly from dvd in a guest domain (I mean without creating & mounting disk image/VM partition and copying root file system in it? If yes, how ? Thanks for your replyes. -- Guillaume

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RE: [Fedora-xen] problem creating my 1st VM
by Dustin Henning 26 Oct '07

26 Oct '07

There is no problem using the same kernel. Some people compile a dom0 kernel and a domU kernel when they custom build or manually install xen, but it isn't necessary, it just makes for a smaller kernel. It is fine to use the same for both, as it is loaded read-only anyway. I was just pointing out that you were using an existing xen kernel in your physical /boot and not a kernel in your vm's /boot. I don't remember all of the setup of paravirtualized vms since it has been a while, but you might try Mike's suggestion: disk = [ 'file:/xenroot/linux/linux.xdi,hda,w' ] in spite of the fact that xmexample1 had hda1 in the second section of the argument. Whether to use hda or hda1 may depend on the image you are using. Also, since Fedora uses an initial ramdisk, you might need to add this line under your kernel line in your config file: ramdisk = "/boot/initrd-2.6.20-2936.fc7xen" Another thing is, notice I am using ' where you used ". I am not sure if it matters, but I think all of my configs have ' instead of " when inside of []s. Finally, you might need to set up a swap partition. If that was necessary, it would probably mean that you need something more like this: disk = [ 'file:/xenroot/linux/linux.xdi,hda1,w' , 'file:/xenroot/linux/linuxswap.xdi,hda2,w' ] In this example, the linuxswap.xdi would have to be loop-mounted and formatted as swap. Keep in mind that it has been a long time since I have dealt with a paravirtualized guest, and also I am not even familiar with the xdi extension / type of file you are using / where it came from and what documentation it came with. It may be that something on your linux.xdi image isn't xen compatible (perhaps the image was made for hvm), though, and that is why I mentioned downloadable xen-ready images (I was running paravirtualized CentOS on an Ubuntu host with xen manually installed [xen xen kernel vs fedora xen kernel or ubuntu xen kernel]). I doubt I come up with any other ideas on your current situation, but if any of these ideas change anything for you, new information might get you some help from someone else. Dustin -----Original Message----- From: Guillaume [mailto:guillaume.chardin@gmail.com] Sent: Friday, October 26, 2007 11:20 To: Dustin.Henning(a)prd-inc.com Subject: Re: [Fedora-xen] problem creating my 1st VM 2007/10/26, Dustin Henning <Dustin.Henning(a)prd-inc.com>: > It has been a while since I have used a paravirtualized vm, so my responses > will be vague, but perhaps helpful. > Regarding your original install, both previous responses made good points. > However, I thought some additional explanation might be helpful: > a) > -The kernel line you put in your config makes your vm boot that kernel (the > one on your local disk), so you are already using a xen kernel to boot that > vm. Is there a problem by using the kernel use to boot up the system (Dom0) ? If I understand, you mean that I have to use a kernel dedicated to boot all DomU ! Why, is there some limitation by using this kernel (Dom0) for running VM ? > -There are ready made xen compatible installs of OSes on disk images > available for download at various places, you should be able to find > instructions on how to get thee images into your vm's virtual drive as well. Ok, but I want first, understand how Xen works, and then, i'll get theses files. I prefer to learn by getting rid of theses problem before, its a godd formation i think. And i tought too, it's more quick to use ready-to-use Xen images files. Thanks for your time :) -- Guillaume

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2011

2010

2009

2008

2007

2006

2005

xen October 2007