Ian Murray
2013-Jul-24 18:22 UTC
Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
Hi, I am trying to create a new domain (Ubuntu 12.04 64 bit) but the installer is starting up crashed. This is on Xen 4.3 but on a previous version of Xen (can''t remember exactly - post 4.1), I was successful using this config file and the same Ubuntu kernel installer files. In fact the resultant domU from the first time still works fine. Config file is... name = "ubuntu-email" memory = 1024 disk = [''phy:/dev/xen6/ubuntu-email,xvda,w'' ] vif = [ ''mac=00:16:31:xx:xx:xx'' ] kernel = "/root/xen/ubuntu1204-64/vmlinuz" ramdisk = "/root/xen/ubuntu1204-64/initrd.gz" vcpus = 2 on_reboot = ''destroy'' on_crash = ''destroy'' When I set it to on_crash = ''preserve'',and I try to create it, I get.... root@xen6:/var/log/xen# xl create -c /etc/xen/ubuntu-email-install Parsing config from /etc/xen/ubuntu-email-install Daemon running with PID 12086 libxl: error: libxl_dom.c:35:libxl__domain_type: unable to get domain type for domid=34 Unable to attach console libxl: error: libxl_exec.c:118:libxl_report_child_exitstatus: console child [0] exited with error status 1 xl list yields... ubuntu-vpndns 33 1256 1 ---sc- 0.1 xl -vvvvvv create yields... root@xen6:/var/log/xen# xl -vvvvvvv create -c /etc/xen/ubuntu-email-install Parsing config from /etc/xen/ubuntu-email-install libxl: debug: libxl_create.c:1230:do_domain_create: ao 0x12de690: create: how=(nil) callback=(nil) poller=0x12de6f0 libxl: debug: libxl_device.c:257:libxl__device_disk_set_backend: Disk vdev=xvda spec.backend=unknown libxl: debug: libxl_device.c:296:libxl__device_disk_set_backend: Disk vdev=xvda, using backend phy libxl: debug: libxl_create.c:675:initiate_domain_create: running bootloader libxl: debug: libxl_bootloader.c:327:libxl__bootloader_run: no bootloader configured, using user supplied kernel libxl: debug: libxl_event.c:608:libxl__ev_xswatch_deregister: watch w=0x12d4118: deregister unregistered libxl: debug: libxl_numa.c:475:libxl__get_numa_candidate: New best NUMA placement candidate found: nr_nodes=1, nr_cpus=2, nr_vcpus=5, free_memkb=14844 libxl: detail: libxl_dom.c:195:numa_place_domain: NUMA placement candidate with 1 nodes, 2 cpus and 14844 KB free selected domainbuilder: detail: xc_dom_allocate: cmdline="", features="(null)" libxl: debug: libxl_dom.c:341:libxl__build_pv: pv kernel mapped 0 path /root/xen/ubuntu1204-64/vmlinuz domainbuilder: detail: xc_dom_kernel_file: filename="/root/xen/ubuntu1204-64/vmlinuz" domainbuilder: detail: xc_dom_malloc_filemap : 4849 kB domainbuilder: detail: xc_dom_ramdisk_file: filename="/root/xen/ubuntu1204-64/initrd.gz" domainbuilder: detail: xc_dom_malloc_filemap : 30178 kB domainbuilder: detail: xc_dom_boot_xen_init: ver 4.3, caps xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 hvm-3.0-x86_32p hvm-3.0-x86_64 domainbuilder: detail: xc_dom_parse_image: called domainbuilder: detail: xc_dom_find_loader: trying multiboot-binary loader ... domainbuilder: detail: loader probe failed domainbuilder: detail: xc_dom_find_loader: trying Linux bzImage loader ... domainbuilder: detail: xc_dom_malloc : 18254 kB domainbuilder: detail: xc_dom_do_gunzip: unzip ok, 0x4b34e6 -> 0x11d3aa0 domainbuilder: detail: loader probe OK xc: detail: elf_parse_binary: phdr: paddr=0x1000000 memsz=0xad5000 xc: detail: elf_parse_binary: phdr: paddr=0x1c00000 memsz=0xe50e0 xc: detail: elf_parse_binary: phdr: paddr=0x1ce6000 memsz=0x14480 xc: detail: elf_parse_binary: phdr: paddr=0x1cfb000 memsz=0x364000 xc: detail: elf_parse_binary: memory: 0x1000000 -> 0x205f000 xc: detail: elf_xen_parse_note: GUEST_OS = "linux" xc: detail: elf_xen_parse_note: GUEST_VERSION = "2.6" xc: detail: elf_xen_parse_note: XEN_VERSION = "xen-3.0" xc: detail: elf_xen_parse_note: VIRT_BASE = 0xffffffff80000000 xc: detail: elf_xen_parse_note: ENTRY = 0xffffffff81cfb200 xc: detail: elf_xen_parse_note: HYPERCALL_PAGE = 0xffffffff81001000 xc: detail: elf_xen_parse_note: FEATURES = "!writable_page_tables|pae_pgdir_above_4gb" xc: detail: elf_xen_parse_note: PAE_MODE = "yes" xc: detail: elf_xen_parse_note: LOADER = "generic" xc: detail: elf_xen_parse_note: unknown xen elf note (0xd) xc: detail: elf_xen_parse_note: SUSPEND_CANCEL = 0x1 xc: detail: elf_xen_parse_note: HV_START_LOW = 0xffff800000000000 xc: detail: elf_xen_parse_note: PADDR_OFFSET = 0x0 xc: detail: elf_xen_addr_calc_check: addresses: xc: detail: virt_base = 0xffffffff80000000 xc: detail: elf_paddr_offset = 0x0 xc: detail: virt_offset = 0xffffffff80000000 xc: detail: virt_kstart = 0xffffffff81000000 xc: detail: virt_kend = 0xffffffff8205f000 xc: detail: virt_entry = 0xffffffff81cfb200 xc: detail: p2m_base = 0xffffffffffffffff domainbuilder: detail: xc_dom_parse_elf_kernel: xen-3.0-x86_64: 0xffffffff81000000 -> 0xffffffff8205f000 domainbuilder: detail: xc_dom_mem_init: mem 1024 MB, pages 0x40000 pages, 4k each domainbuilder: detail: xc_dom_mem_init: 0x40000 pages domainbuilder: detail: xc_dom_boot_mem_init: called domainbuilder: detail: x86_compat: guest xen-3.0-x86_64, address size 64 domainbuilder: detail: xc_dom_malloc : 2048 kB domainbuilder: detail: xc_dom_build_image: called domainbuilder: detail: xc_dom_alloc_segment: kernel : 0xffffffff81000000 -> 0xffffffff8205f000 (pfn 0x1000 + 0x105f pages) domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 0x1000+0x105f at 0x7faa7d68f000 xc: detail: elf_load_binary: phdr 0 at 0x7faa7d68f000 -> 0x7faa7e164000 xc: detail: elf_load_binary: phdr 1 at 0x7faa7e28f000 -> 0x7faa7e3740e0 xc: detail: elf_load_binary: phdr 2 at 0x7faa7e375000 -> 0x7faa7e389480 xc: detail: elf_load_binary: phdr 3 at 0x7faa7e38a000 -> 0x7faa7e462000 domainbuilder: detail: xc_dom_alloc_segment: ramdisk : 0xffffffff8205f000 -> 0xffffffff86b0a000 (pfn 0x205f + 0x4aab pages) domainbuilder: detail: xc_dom_malloc : 448 kB domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 0x205f+0x4aab at 0x7faa78be4000 domainbuilder: detail: xc_dom_do_gunzip: unzip ok, 0x1d78b44 -> 0x4aaa810 domainbuilder: detail: xc_dom_alloc_segment: phys2mach : 0xffffffff86b0a000 -> 0xffffffff86d0a000 (pfn 0x6b0a + 0x200 pages) domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 0x6b0a+0x200 at 0x7faa789e4000 domainbuilder: detail: xc_dom_alloc_page : start info : 0xffffffff86d0a000 (pfn 0x6d0a) domainbuilder: detail: xc_dom_alloc_page : xenstore : 0xffffffff86d0b000 (pfn 0x6d0b) domainbuilder: detail: xc_dom_alloc_page : console : 0xffffffff86d0c000 (pfn 0x6d0c) domainbuilder: detail: nr_page_tables: 0x0000ffffffffffff/48: 0xffff000000000000 -> 0xffffffffffffffff, 1 table(s) domainbuilder: detail: nr_page_tables: 0x0000007fffffffff/39: 0xffffff8000000000 -> 0xffffffffffffffff, 1 table(s) domainbuilder: detail: nr_page_tables: 0x000000003fffffff/30: 0xffffffff80000000 -> 0xffffffffbfffffff, 1 table(s) domainbuilder: detail: nr_page_tables: 0x00000000001fffff/21: 0xffffffff80000000 -> 0xffffffff86ffffff, 56 table(s) domainbuilder: detail: xc_dom_alloc_segment: page tables : 0xffffffff86d0d000 -> 0xffffffff86d48000 (pfn 0x6d0d + 0x3b pages) domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 0x6d0d+0x3b at 0x7faa83b34000 domainbuilder: detail: xc_dom_alloc_page : boot stack : 0xffffffff86d48000 (pfn 0x6d48) domainbuilder: detail: xc_dom_build_image : virt_alloc_end : 0xffffffff86d49000 domainbuilder: detail: xc_dom_build_image : virt_pgtab_end : 0xffffffff87000000 domainbuilder: detail: xc_dom_boot_image: called domainbuilder: detail: arch_setup_bootearly: doing nothing domainbuilder: detail: xc_dom_compat_check: supported guest type: xen-3.0-x86_64 <= matches domainbuilder: detail: xc_dom_compat_check: supported guest type: xen-3.0-x86_32p domainbuilder: detail: xc_dom_compat_check: supported guest type: hvm-3.0-x86_32 domainbuilder: detail: xc_dom_compat_check: supported guest type: hvm-3.0-x86_32p domainbuilder: detail: xc_dom_compat_check: supported guest type: hvm-3.0-x86_64 domainbuilder: detail: xc_dom_update_guest_p2m: dst 64bit, pages 0x40000 domainbuilder: detail: clear_page: pfn 0x6d0c, mfn 0x2f06bb domainbuilder: detail: clear_page: pfn 0x6d0b, mfn 0x2f06bc domainbuilder: detail: xc_dom_pfn_to_ptr_retcount: domU mapping: pfn 0x6d0a+0x1 at 0x7faa83b31000 domainbuilder: detail: start_info_x86_64: called domainbuilder: detail: setup_hypercall_page: vaddr=0xffffffff81001000 pfn=0x1001 domainbuilder: detail: domain builder memory footprint domainbuilder: detail: allocated domainbuilder: detail: malloc : 20865 kB domainbuilder: detail: anon mmap : 0 bytes domainbuilder: detail: mapped domainbuilder: detail: file mmap : 34 MB domainbuilder: detail: domU mmap : 93 MB domainbuilder: detail: arch_setup_bootlate: shared_info: pfn 0x0, mfn 0xdaa21 domainbuilder: detail: shared_info_x86_64: called domainbuilder: detail: vcpu_x86_64: called domainbuilder: detail: vcpu_x86_64: cr3: pfn 0x6d0d mfn 0x2f06ba domainbuilder: detail: launch_vm: called, ctxt=0x7fff267abd00 domainbuilder: detail: xc_dom_release: called libxl: debug: libxl_device.c:257:libxl__device_disk_set_backend: Disk vdev=xvda spec.backend=phy libxl: debug: libxl_event.c:559:libxl__ev_xswatch_register: watch w=0x12da608 wpath=/local/domain/0/backend/vbd/37/51712/state token=3/0: register slotnum=3 libxl: debug: libxl_create.c:1243:do_domain_create: ao 0x12de690: inprogress: poller=0x12de6f0, flags=i libxl: debug: libxl_event.c:503:watchfd_callback: watch w=0x12da608 wpath=/local/domain/0/backend/vbd/37/51712/state token=3/0: event epath=/local/domain/0/backend/vbd/37/51712/state libxl: debug: libxl_event.c:647:devstate_watch_callback: backend /local/domain/0/backend/vbd/37/51712/state wanted state 2 still waiting state 1 libxl: debug: libxl_event.c:503:watchfd_callback: watch w=0x12da608 wpath=/local/domain/0/backend/vbd/37/51712/state token=3/0: event epath=/local/domain/0/backend/vbd/37/51712/state libxl: debug: libxl_event.c:643:devstate_watch_callback: backend /local/domain/0/backend/vbd/37/51712/state wanted state 2 ok libxl: debug: libxl_event.c:596:libxl__ev_xswatch_deregister: watch w=0x12da608 wpath=/local/domain/0/backend/vbd/37/51712/state token=3/0: deregister slotnum=3 libxl: debug: libxl_event.c:608:libxl__ev_xswatch_deregister: watch w=0x12da608: deregister unregistered libxl: debug: libxl_device.c:959:device_hotplug: calling hotplug script: /etc/xen/scripts/block add libxl: debug: libxl_event.c:559:libxl__ev_xswatch_register: watch w=0x12dc2c8 wpath=/local/domain/0/backend/vif/37/0/state token=3/1: register slotnum=3 libxl: debug: libxl_event.c:503:watchfd_callback: watch w=0x12dc2c8 wpath=/local/domain/0/backend/vif/37/0/state token=3/1: event epath=/local/domain/0/backend/vif/37/0/state libxl: debug: libxl_event.c:643:devstate_watch_callback: backend /local/domain/0/backend/vif/37/0/state wanted state 2 ok libxl: debug: libxl_event.c:596:libxl__ev_xswatch_deregister: watch w=0x12dc2c8 wpath=/local/domain/0/backend/vif/37/0/state token=3/1: deregister slotnum=3 libxl: debug: libxl_event.c:608:libxl__ev_xswatch_deregister: watch w=0x12dc2c8: deregister unregistered libxl: debug: libxl_device.c:959:device_hotplug: calling hotplug script: /etc/xen/scripts/vif-bridge online libxl: debug: libxl_event.c:472:watchfd_callback: watch epath=/local/domain/0/backend/vif/37/0/state token=3/1: empty slot libxl: debug: libxl_event.c:1747:libxl__ao_progress_report: ao 0x12de690: progress report: callback queued aop=0x12dd790 libxl: debug: libxl_event.c:1569:libxl__ao_complete: ao 0x12de690: complete, rc=0 libxl: debug: libxl_event.c:1160:egc_run_callbacks: ao 0x12de690: progress report: callback aop=0x12dd790 libxl: debug: libxl_event.c:1541:libxl__ao__destroy: ao 0x12de690: destroy Daemon running with PID 12734 xc: debug: hypercall buffer: total allocations:496 total releases:496 xc: debug: hypercall buffer: current allocations:0 maximum allocations:4 xc: debug: hypercall buffer: cache current size:4 xc: debug: hypercall buffer: cache hits:486 misses:4 toobig:6 root@xen6:/var/log/xen# xl list Name ID Mem VCPUs State Time(s) Domain-0 0 1021 2 r----- 985.3 ubuntu-email 37 1024 1 ---sc- 0.1 Looking at the logs yields.... root@xen6:/var/log/xen# cat xl-ubuntu-email.log Waiting for domain ubuntu-email (domid 37) to die [pid 12735] libxl: debug: libxl_event.c:559:libxl__ev_xswatch_register: watch w=0x12da610 wpath=@releaseDomain token=3/0: register slotnum=3 libxl: debug: libxl_event.c:503:watchfd_callback: watch w=0x12da610 wpath=@releaseDomain token=3/0: event epath=@releaseDomain libxl: debug: libxl.c:999:domain_death_xswatch_callback: [evg=0x12da420:37] from domid=37 nentries=1 rc=1 libxl: debug: libxl.c:1010:domain_death_xswatch_callback: [evg=0x12da420:37] got=domaininfos[0] got->domain=37 libxl: debug: libxl.c:1037:domain_death_xswatch_callback: exists shutdown_reported=0 dominf.flags=ffff0020 libxl: debug: libxl.c:1003:domain_death_xswatch_callback: [evg=0] all reported libxl: debug: libxl.c:1067:domain_death_xswatch_callback: domain death search done libxl: debug: libxl_event.c:503:watchfd_callback: watch w=0x12da610 wpath=@releaseDomain token=3/0: event epath=@releaseDomain libxl: debug: libxl.c:999:domain_death_xswatch_callback: [evg=0x12da420:37] from domid=37 nentries=1 rc=1 libxl: debug: libxl.c:1010:domain_death_xswatch_callback: [evg=0x12da420:37] got=domaininfos[0] got->domain=37 libxl: debug: libxl.c:1037:domain_death_xswatch_callback: exists shutdown_reported=0 dominf.flags=30004 libxl: debug: libxl.c:1049:domain_death_xswatch_callback: shutdown reporting libxl: debug: libxl.c:1003:domain_death_xswatch_callback: [evg=0] all reported libxl: debug: libxl.c:1067:domain_death_xswatch_callback: domain death search done Domain 37 has shut down, reason code 3 0x3 Action for shutdown reason code 3 is preserve Done. Exiting now libxl: debug: libxl_event.c:596:libxl__ev_xswatch_deregister: watch w=0x12da610 wpath=@releaseDomain token=3/0: deregister slotnum=3 xc: debug: hypercall buffer: total allocations:4 total releases:4 xc: debug: hypercall buffer: current allocations:0 maximum allocations:2 xc: debug: hypercall buffer: cache current size:2 xc: debug: hypercall buffer: cache hits:2 misses:2 toobig:0 root@xen6:/var/log/xen# Any suggestions would be greatly received. Thanks, Ian. _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
Ian Murray
2013-Jul-24 18:33 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
>________________________________ > From: Ian Murray <murrayie@yahoo.co.uk> >To: "xen-users@lists.xensource.com" <xen-users@lists.xensource.com> >Sent: Wednesday, 24 July 2013, 19:22 >Subject: [Xen-users] Trying to create new domain on 4.3 but domU is starting crashed (-sc-) > > > >Hi, > > >I am trying to create a new domain (Ubuntu 12.04 64 bit) but the installer is starting up crashed. This is on Xen 4.3 but on a previous version of Xen (can''t remember exactly - post 4.1), I was successful using this config file and the same Ubuntu kernel installer files. In fact the resultant domU from the first time still works fine. > > > >Config file is... > > >name = "ubuntu-email" >memory = 1024 >disk = [''phy:/dev/xen6/ubuntu-email,xvda,w'' ] >vif = [ ''mac=00:16:31:xx:xx:xx'' ] >kernel = "/root/xen/ubuntu1204-64/vmlinuz" >ramdisk = "/root/xen/ubuntu1204-64/initrd.gz" >vcpus = 2 >on_reboot = ''destroy'' >on_crash = ''destroy'' >If I substitute 13.04''s xen installer files, it starts fine. I remember someone else having this trouble with 12.04 (on pre-Xen 4.3). I remember replying something along the lines of "works for me", along with checksums of my installer files and some other helpful bits.) I have no idea why things may have changed for me.
Ian Campbell
2013-Jul-24 18:36 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
On Wed, 2013-07-24 at 19:22 +0100, Ian Murray wrote:> Any suggestions would be greatly received.Do you get anything out of the guest console? I think if you set on_crash = "preserve" you can still use "xl console" after the crash or else you can configure xenconsoled to log as per: http://wiki.xen.org/wiki/Reporting_Bugs_against_Xen#Guest_console_logs Ian.
Ian Murray
2013-Jul-24 19:07 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
----- Original Message -----> From: Ian Campbell <ian.campbell@citrix.com> > To: Ian Murray <murrayie@yahoo.co.uk> > Cc: "xen-users@lists.xensource.com" <xen-users@lists.xensource.com> > Sent: Wednesday, 24 July 2013, 19:36 > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU is starting crashed (-sc-) > > On Wed, 2013-07-24 at 19:22 +0100, Ian Murray wrote: >> Any suggestions would be greatly received. > > Do you get anything out of the guest console? I think if you set > on_crash = "preserve" > you can still use "xl console" after the crash or else you can > configure > xenconsoled to log as per: > http://wiki.xen.org/wiki/Reporting_Bugs_against_Xen#Guest_console_logsThanks for the reply, Ian. I tried both of these and got nothing. xl console <nn> just hangs until the ctrl-] out of it and I get no file produced with the xenconsoled log (didn''t get anything for a working domain, either, so I need to re-check I did that right). I can''t help feeling there is a longstanding problem with 12.04 Ubuntu Xen install files. I tried 64 bit and 32 bits version, same behaviour. I re-read the other thread and the other guy had exactly the same problem but resolved it by using some Ubuntu Xen creation tool. He was using Xen 4.2.1 http://lists.xen.org/archives/html/xen-users/2013-02/msg00236.html Dom0''s kernerl is not up-to-date, so I will try to update that before I go any further. Thanks again, Ian> > Ian. > > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xen.org > http://lists.xen.org/xen-users >
Ian Campbell
2013-Jul-25 03:37 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
On Wed, 2013-07-24 at 20:07 +0100, Ian Murray wrote:> > > > ----- Original Message ----- > > From: Ian Campbell <ian.campbell@citrix.com> > > To: Ian Murray <murrayie@yahoo.co.uk> > > Cc: "xen-users@lists.xensource.com" <xen-users@lists.xensource.com> > > Sent: Wednesday, 24 July 2013, 19:36 > > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU is starting crashed (-sc-) > > > > On Wed, 2013-07-24 at 19:22 +0100, Ian Murray wrote: > >> Any suggestions would be greatly received. > > > > Do you get anything out of the guest console? I think if you set > > on_crash = "preserve" > > you can still use "xl console" after the crash or else you can > > configure > > xenconsoled to log as per: > > http://wiki.xen.org/wiki/Reporting_Bugs_against_Xen#Guest_console_logs > > Thanks for the reply, Ian. > > I tried both of these and got nothing. xl console <nn> just hangs > until the ctrl-] out of it and I get no file produced with the > xenconsoled log (didn''t get anything for a working domain, either, so > I need to re-check I did that right).Not getting anything from a working domain sounds wrong, there should definitely be something. You''ll need to either "service xencommons restart" after editing the sysconfig file or a reboot, in any case it should be apparent in the "ps" output for the xenconsoled command that the argument has taken affect (it should have --mumble=guest where mumble is "trace" or "log" or something like that). Once you are sure of that then you ought to get *something* out of the crashing guest console -- if not then you might try adding "earlyprintk=xen" to the guest kernel command line.> I can''t help feeling there is a longstanding problem with 12.04 Ubuntu > Xen install files. I tried 64 bit and 32 bits version, same behaviour.If you think it might be an Ubuntu bug then trawling Launchpad might be worthwhile. Nothing springs to my mind but that doesn''t really mean much.> I re-read the other thread and the other guy had exactly the same > problem but resolved it by using some Ubuntu Xen creation tool. He was > using Xen 4.2.1Depending on what "some Ubuntu Xen creation tool" is it may well be using some different kernel or something.> http://lists.xen.org/archives/html/xen-users/2013-02/msg00236.html > > Dom0''s kernerl is not up-to-date, so I will try to update that before > I go any further.That can''t hurt, although I wouldn''t hold you breath. Do you get anything on the Xen console (e.g. "xl dmesg")? You might find adding guest_loglvl=all to your h/v command line gets you more here too. Ian.
Ian Murray
2013-Jul-25 09:41 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
----- Original Message -----> From: Ian Campbell <ian.campbell@citrix.com> > To: Ian Murray <murrayie@yahoo.co.uk> > Cc: "xen-users@lists.xensource.com" <xen-users@lists.xensource.com> > Sent: Thursday, 25 July 2013, 4:37 > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU is starting crashed (-sc-) > > On Wed, 2013-07-24 at 20:07 +0100, Ian Murray wrote: >> >> >> >> ----- Original Message ----- >> > From: Ian Campbell <ian.campbell@citrix.com> >> > To: Ian Murray <murrayie@yahoo.co.uk> >> > Cc: "xen-users@lists.xensource.com" > <xen-users@lists.xensource.com> >> > Sent: Wednesday, 24 July 2013, 19:36 >> > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU > is starting crashed (-sc-) >> > >> > On Wed, 2013-07-24 at 19:22 +0100, Ian Murray wrote: >> >> Any suggestions would be greatly received. >> > >> > Do you get anything out of the guest console? I think if you set >> > on_crash = "preserve" >> > you can still use "xl console" after the crash or else you > can >> > configure >> > xenconsoled to log as per: >> > http://wiki.xen.org/wiki/Reporting_Bugs_against_Xen#Guest_console_logs >> >> Thanks for the reply, Ian. >> >> I tried both of these and got nothing. xl console <nn> just hangs >> until the ctrl-] out of it and I get no file produced with the >> xenconsoled log (didn''t get anything for a working domain, either, so >> I need to re-check I did that right). > > Not getting anything from a working domain sounds wrong, there should > definitely be something. You''ll need to either "service xencommons > restart" after editing the sysconfig file or a reboot, in any case it > should be apparent in the "ps" output for the xenconsoled command that > the argument has taken affect (it should have --mumble=guest where > mumble is "trace" or "log" or something like that).root 1526 0.0 0.1 90956 1096 ? SLl Jul24 0:00 /usr/sbin/xenconsoled --pid-file=/var/run/xenconsoled.pid --log=guest I must admit, I never have it straight in my head about hvc0 vs xvc0, etc. earlyprintk=xen doesn''t seem to have made any difference. I am wondering if I did something wrong at compile time (it has been known)> > Once you are sure of that then you ought to get *something* out of the > crashing guest console -- if not then you might try adding > "earlyprintk=xen" to the guest kernel command line. > >> I can''t help feeling there is a longstanding problem with 12.04 Ubuntu >> Xen install files. I tried 64 bit and 32 bits version, same behaviour. > > If you think it might be an Ubuntu bug then trawling Launchpad might be > worthwhile. Nothing springs to my mind but that doesn''t really mean > much. > >> I re-read the other thread and the other guy had exactly the same >> problem but resolved it by using some Ubuntu Xen creation tool. He was >> using Xen 4.2.1 > > Depending on what "some Ubuntu Xen creation tool" is it may well be > using some different kernel or something.He succesfully created it using xen-create-image --hostname=ubuntu \ --memory=512mb \ --vcpus=2 \ --lvm=center \ --dhcp \ --pygrub \ --dist=precise I''ve never used this tool and I prefer to do things distribution agnostically as I have Xen on Ubuntu and Scientific Linux 6.4> >> http://lists.xen.org/archives/html/xen-users/2013-02/msg00236.html >> >> Dom0''s kernerl is not up-to-date, so I will try to update that before >> I go any further. > > That can''t hurt, although I wouldn''t hold you breath.It didn''t hurt but it didn''t help. Was always a long shot.> > Do you get anything on the Xen console (e.g. "xl dmesg")? You might > find > adding guest_loglvl=all to your h/v command line gets you more here too.Nothing very interesting even when I do that... root@xen6:/var/log/xen# xl dmesg __ __ _ _ _____ ___ \ \/ /___ _ __ | || | |___ / / _ \ \ // _ \ ''_ \ | || |_ |_ \| | | | / \ __/ | | | |__ _| ___) | |_| | /_/\_\___|_| |_| |_|(_)____(_)___/ (XEN) Xen version 4.3.0 (root@) (gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3) debug=n Tue Jul 9 16:03:18 BST 2013 (XEN) Latest ChangeSet: Tue Jul 9 11:46:56 2013 +0100 git:f8cc9c2 (XEN) Bootloader: GRUB 1.99-21ubuntu3.9 (XEN) Command line: placeholder dom0_mem=1024M,max:1024M loglvl=all guest_loglvl=all (XEN) Video information: (XEN) VGA is text mode 80x25, font 8x16 (XEN) VBE/DDC methods: none; EDID transfer time: 0 seconds (XEN) EDID info not retrieved because no DDC retrieval method detected (XEN) Disc information: (XEN) Found 1 MBR signatures (XEN) Found 1 EDD information structures (XEN) Xen-e820 RAM map: (XEN) 0000000000000000 - 000000000009d800 (usable) (XEN) 000000000009d800 - 00000000000a0000 (reserved) (XEN) 00000000000e0000 - 0000000000100000 (reserved) (XEN) 0000000000100000 - 0000000020000000 (usable) (XEN) 0000000020000000 - 0000000020200000 (reserved) (XEN) 0000000020200000 - 0000000040000000 (usable) (XEN) 0000000040000000 - 0000000040200000 (reserved) (XEN) 0000000040200000 - 00000000d8c15000 (usable) (XEN) 00000000d8c15000 - 00000000d9314000 (reserved) (XEN) 00000000d9314000 - 00000000d9429000 (ACPI NVS) (XEN) 00000000d9429000 - 00000000da5dc000 (reserved) (XEN) 00000000da5dc000 - 00000000da5dd000 (usable) (XEN) 00000000da5dd000 - 00000000da620000 (ACPI NVS) (XEN) 00000000da620000 - 00000000daa33000 (usable) (XEN) 00000000daa33000 - 00000000daff4000 (reserved) (XEN) 00000000daff4000 - 00000000db000000 (usable) (XEN) 00000000db800000 - 00000000dfa00000 (reserved) (XEN) 00000000f8000000 - 00000000fc000000 (reserved) (XEN) 00000000fec00000 - 00000000fec01000 (reserved) (XEN) 00000000fed00000 - 00000000fed04000 (reserved) (XEN) 00000000fed1c000 - 00000000fed20000 (reserved) (XEN) 00000000fee00000 - 00000000fee01000 (reserved) (XEN) 00000000ff000000 - 0000000100000000 (reserved) (XEN) 0000000100000000 - 000000041e600000 (usable) (XEN) ACPI: RSDP 000F0490, 0024 (r2 ALASKA) (XEN) ACPI: XSDT D941A078, 006C (r1 ALASKA A M I 1072009 AMI 10013) (XEN) ACPI: FACP D9423D80, 010C (r5 ALASKA A M I 1072009 AMI 10013) (XEN) ACPI: DSDT D941A178, 9C03 (r2 ALASKA A M I 21 INTL 20051117) (XEN) ACPI: FACS D9427080, 0040 (XEN) ACPI: APIC D9423E90, 0062 (r3 ALASKA A M I 1072009 AMI 10013) (XEN) ACPI: FPDT D9423EF8, 0044 (r1 ALASKA A M I 1072009 AMI 10013) (XEN) ACPI: MCFG D9423F40, 003C (r1 ALASKA A M I 1072009 MSFT 97) (XEN) ACPI: HPET D9423F80, 0038 (r1 ALASKA A M I 1072009 AMI. 5) (XEN) ACPI: SSDT D9423FB8, 036D (r1 SataRe SataTabl 1000 INTL 20091112) (XEN) ACPI: SSDT D9424328, 0926 (r1 PmRef Cpu0Ist 3000 INTL 20051117) (XEN) ACPI: SSDT D9424C50, 0A92 (r1 PmRef CpuPm 3000 INTL 20051117) (XEN) ACPI: ASF! D94256E8, 00A5 (r32 INTEL HCG 1 TFSM F4240) (XEN) System RAM: 16241MB (16631624kB) (XEN) No NUMA configuration found (XEN) Faking a node at 0000000000000000-000000041e600000 (XEN) Domain heap initialised (XEN) found SMP MP-table at 000fd750 (XEN) DMI 2.7 present. (XEN) Using APIC driver default (XEN) ACPI: PM-Timer IO Port: 0x408 (XEN) ACPI: v5 SLEEP INFO: control[0:0], status[0:0] (XEN) ACPI: SLEEP INFO: pm1x_cnt[404,0], pm1x_evt[400,0] (XEN) ACPI: 32/64X FACS address mismatch in FADT - d9427080/0000000000000000, using 32 (XEN) ACPI: wakeup_vec[d942708c], vec_size[20] (XEN) ACPI: Local APIC address 0xfee00000 (XEN) ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled) (XEN) Processor #0 6:10 APIC version 21 (XEN) ACPI: LAPIC (acpi_id[0x02] lapic_id[0x02] enabled) (XEN) Processor #2 6:10 APIC version 21 (XEN) ACPI: LAPIC_NMI (acpi_id[0xff] high edge lint[0x1]) (XEN) ACPI: IOAPIC (id[0x02] address[0xfec00000] gsi_base[0]) (XEN) IOAPIC[0]: apic_id 2, version 32, address 0xfec00000, GSI 0-23 (XEN) ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl) (XEN) ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level) (XEN) ACPI: IRQ0 used by override. (XEN) ACPI: IRQ2 used by override. (XEN) ACPI: IRQ9 used by override. (XEN) Enabling APIC mode: Flat. Using 1 I/O APICs (XEN) ACPI: HPET id: 0x8086a701 base: 0xfed00000 (XEN) ERST table was not found (XEN) Using ACPI (MADT) for SMP configuration information (XEN) SMP: Allowing 2 CPUs (0 hotplug CPUs) (XEN) IRQ limits: 24 GSI, 376 MSI/MSI-X (XEN) Using scheduler: SMP Credit Scheduler (credit) (XEN) Detected 2893.511 MHz processor. (XEN) Initing memory sharing. (XEN) xstate_init: using cntxt_size: 0x240 and states: 0x3 (XEN) mce_intel.c:717: MCA Capability: BCAST 1 SER 0 CMCI 1 firstbank 0 extended MCE MSR 0 (XEN) Intel machine check reporting enabled (XEN) PCI: MCFG configuration 0: base f8000000 segment 0000 buses 00 - 3f (XEN) PCI: MCFG area at f8000000 reserved in E820 (XEN) PCI: Using MCFG for segment 0000 bus 00-3f (XEN) I/O virtualisation disabled (XEN) Enabled directed EOI with ioapic_ack_old on! (XEN) ENABLING IO-APIC IRQs (XEN) -> Using old ACK method (XEN) ..TIMER: vector=0xF0 apic1=0 pin1=2 apic2=-1 pin2=-1 (XEN) TSC deadline timer enabled (XEN) Platform timer is 14.318MHz HPET (XEN) Allocated console ring of 16 KiB. (XEN) mwait-idle: MWAIT substates: 0x1120 (XEN) mwait-idle: v0.4 model 0x2a (XEN) mwait-idle: lapic_timer_reliable_states 0xffffffff (XEN) VMX: Supported advanced features: (XEN) - APIC MMIO access virtualisation (XEN) - APIC TPR shadow (XEN) - Extended Page Tables (EPT) (XEN) - Virtual-Processor Identifiers (VPID) (XEN) - Virtual NMI (XEN) - MSR direct-access bitmap (XEN) - Unrestricted Guest (XEN) HVM: ASIDs enabled. (XEN) HVM: VMX enabled (XEN) HVM: Hardware Assisted Paging (HAP) detected (XEN) HVM: HAP page sizes: 4kB, 2MB (XEN) Brought up 2 CPUs (XEN) ACPI sleep modes: S3 (XEN) mcheck_poll: Machine check polling timer started. (XEN) *** LOADING DOMAIN 0 *** (XEN) Xen kernel: 64-bit, lsb, compat32 (XEN) Dom0 kernel: 64-bit, PAE, lsb, paddr 0x1000000 -> 0x2060000 (XEN) PHYSICAL MEMORY ARRANGEMENT: (XEN) Dom0 alloc.: 0000000408000000->000000040c000000 (235679 pages to be allocated) (XEN) Init. ramdisk: 000000041be9f000->000000041e5ff400 (XEN) VIRTUAL MEMORY ARRANGEMENT: (XEN) Loaded kernel: ffffffff81000000->ffffffff82060000 (XEN) Init. ramdisk: ffffffff82060000->ffffffff847c0400 (XEN) Phys-Mach map: ffffffff847c1000->ffffffff849c1000 (XEN) Start info: ffffffff849c1000->ffffffff849c14b4 (XEN) Page tables: ffffffff849c2000->ffffffff849eb000 (XEN) Boot stack: ffffffff849eb000->ffffffff849ec000 (XEN) TOTAL: ffffffff80000000->ffffffff84c00000 (XEN) ENTRY ADDRESS: ffffffff81cfc200 (XEN) Dom0 has maximum 2 VCPUs (XEN) Scrubbing Free RAM: ......................................................................................................................................................done. (XEN) Initial low memory virq threshold set at 0x4000 pages. (XEN) Std. Loglevel: All (XEN) Guest Loglevel: All (XEN) Xen is relinquishing VGA console. (XEN) *** Serial input -> DOM0 (type ''CTRL-a'' three times to switch input to Xen) (XEN) Freed 264kB init memory. (XEN) PCI add device 0000:00:00.0 (XEN) PCI add device 0000:00:02.0 (XEN) PCI add device 0000:00:14.0 (XEN) PCI add device 0000:00:16.0 (XEN) PCI add device 0000:00:1a.0 (XEN) PCI add device 0000:00:1b.0 (XEN) PCI add device 0000:00:1c.0 (XEN) PCI add device 0000:00:1c.1 (XEN) PCI add device 0000:00:1d.0 (XEN) PCI add device 0000:00:1e.0 (XEN) PCI add device 0000:00:1f.0 (XEN) PCI add device 0000:00:1f.2 (XEN) PCI add device 0000:00:1f.3 (XEN) PCI add device 0000:02:00.0 root@xen6:/var/log/xen#> > Ian. >I repeated the exercise on my SL machine which worked fine. This is running Xen 4.2.2 (compiled from tar rather than git rep), although I wouldn''t read too much into this because the other person was having similar issues using 4.2.1. Having said that, his issues went away when he reverted back to 4.1.x I am going to revert this machine back to 4.2.2 to see what happens.> > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xen.org > http://lists.xen.org/xen-users >
Ian Murray
2013-Jul-25 12:17 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
> I am going to revert this machine back to 4.2.2 to see what happens. >In fact, I went back to 4.2.1 and this made no difference.
Ian Campbell
2013-Jul-26 12:44 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
On Thu, 2013-07-25 at 10:41 +0100, Ian Murray wrote:> > > > ----- Original Message ----- > > From: Ian Campbell <ian.campbell@citrix.com> > > To: Ian Murray <murrayie@yahoo.co.uk> > > Cc: "xen-users@lists.xensource.com" <xen-users@lists.xensource.com> > > Sent: Thursday, 25 July 2013, 4:37 > > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU is starting crashed (-sc-) > > > > On Wed, 2013-07-24 at 20:07 +0100, Ian Murray wrote: > >> > >> > >> > >> ----- Original Message ----- > >> > From: Ian Campbell <ian.campbell@citrix.com> > >> > To: Ian Murray <murrayie@yahoo.co.uk> > >> > Cc: "xen-users@lists.xensource.com" > > <xen-users@lists.xensource.com> > >> > Sent: Wednesday, 24 July 2013, 19:36 > >> > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU > > is starting crashed (-sc-) > >> > > >> > On Wed, 2013-07-24 at 19:22 +0100, Ian Murray wrote: > >> >> Any suggestions would be greatly received. > >> > > >> > Do you get anything out of the guest console? I think if you set > >> > on_crash = "preserve" > >> > you can still use "xl console" after the crash or else you > > can > >> > configure > >> > xenconsoled to log as per: > >> > http://wiki.xen.org/wiki/Reporting_Bugs_against_Xen#Guest_console_logs > >> > >> Thanks for the reply, Ian. > >> > >> I tried both of these and got nothing. xl console <nn> just hangs > >> until the ctrl-] out of it and I get no file produced with the > >> xenconsoled log (didn''t get anything for a working domain, either, so > >> I need to re-check I did that right). > > > > Not getting anything from a working domain sounds wrong, there should > > definitely be something. You''ll need to either "service xencommons > > restart" after editing the sysconfig file or a reboot, in any case it > > should be apparent in the "ps" output for the xenconsoled command that > > the argument has taken affect (it should have --mumble=guest where > > mumble is "trace" or "log" or something like that). > > root 1526 0.0 0.1 90956 1096 ? SLl Jul24 0:00 /usr/sbin/xenconsoled --pid-file=/var/run/xenconsoled.pid --log=guest > > I must admit, I never have it straight in my head about hvc0 vs xvc0, etc. earlyprintk=xen doesn''t seem to have made any difference. > > I am wondering if I did something wrong at compile time (it has been known)If with a known good domain you don''t get anything under /var/log/xen/consoles/ then I don''t know what is going on. With any modern kernel console=hvc0 is what you want, if your kernel is old but not a complete relic then "console=hvc0 xencons=hvc" should work.> > > > Once you are sure of that then you ought to get *something* out of the > > crashing guest console -- if not then you might try adding > > "earlyprintk=xen" to the guest kernel command line. > > > >> I can''t help feeling there is a longstanding problem with 12.04 Ubuntu > >> Xen install files. I tried 64 bit and 32 bits version, same behaviour. > > > > If you think it might be an Ubuntu bug then trawling Launchpad might be > > worthwhile. Nothing springs to my mind but that doesn''t really mean > > much. > > > >> I re-read the other thread and the other guy had exactly the same > >> problem but resolved it by using some Ubuntu Xen creation tool. He was > >> using Xen 4.2.1 > > > > Depending on what "some Ubuntu Xen creation tool" is it may well be > > using some different kernel or something. > > He succesfully created it using > > > xen-create-image --hostname=ubuntu \ > --memory=512mb \ > --vcpus=2 \ > --lvm=center \ > --dhcp \ > --pygrub \ > --dist=precise > > I''ve never used this tool and I prefer to do things distribution agnostically as I have Xen on Ubuntu and Scientific Linux 6.4Right. The approach above is bascially debbootstrap + using the dom0 kernel (which you can be reasonably sure is correct). One experiment you could try is to extract the kernel from your guest image and try booting it via the "dom0 path" method. Ian.
Ian Murray
2013-Aug-01 16:04 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
----- Original Message -----> From: Ian Campbell <ian.campbell@citrix.com> > To: Ian Murray <murrayie@yahoo.co.uk> > Cc: "xen-users@lists.xensource.com" <xen-users@lists.xensource.com> > Sent: Friday, 26 July 2013, 13:44 > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU is starting crashed (-sc-) > > On Thu, 2013-07-25 at 10:41 +0100, Ian Murray wrote: >> >> >> >> ----- Original Message ----- >> > From: Ian Campbell <ian.campbell@citrix.com> >> > To: Ian Murray <murrayie@yahoo.co.uk> >> > Cc: "xen-users@lists.xensource.com" > <xen-users@lists.xensource.com> >> > Sent: Thursday, 25 July 2013, 4:37 >> > Subject: Re: [Xen-users] Trying to create new domain on 4.3 but domU > is starting crashed (-sc-) >> > >> > On Wed, 2013-07-24 at 20:07 +0100, Ian Murray wrote: >> >> >> >> >> >> >> >> ----- Original Message ----- >> >> > From: Ian Campbell <ian.campbell@citrix.com> >> >> > To: Ian Murray <murrayie@yahoo.co.uk> >> >> > Cc: "xen-users@lists.xensource.com" >> > <xen-users@lists.xensource.com> >> >> > Sent: Wednesday, 24 July 2013, 19:36 >> >> > Subject: Re: [Xen-users] Trying to create new domain on 4.3 > but domU >> > is starting crashed (-sc-) >> >> > >> >> > On Wed, 2013-07-24 at 19:22 +0100, Ian Murray wrote: >> >> >> Any suggestions would be greatly received. >> >> > >> >> > Do you get anything out of the guest console? I think if you > set >> >> > on_crash = "preserve" >> >> > you can still use "xl console" after the crash or > else you >> > can >> >> > configure >> >> > xenconsoled to log as per: >> >> > > http://wiki.xen.org/wiki/Reporting_Bugs_against_Xen#Guest_console_logs >> >> >> >> Thanks for the reply, Ian. >> >> >> >> I tried both of these and got nothing. xl console <nn> just > hangs >> >> until the ctrl-] out of it and I get no file produced with the >> >> xenconsoled log (didn''t get anything for a working domain, > either, so >> >> I need to re-check I did that right). >> > >> > Not getting anything from a working domain sounds wrong, there should >> > definitely be something. You''ll need to either "service > xencommons >> > restart" after editing the sysconfig file or a reboot, in any > case it >> > should be apparent in the "ps" output for the xenconsoled > command that >> > the argument has taken affect (it should have --mumble=guest where >> > mumble is "trace" or "log" or something like > that). >> >> root 1526 0.0 0.1 90956 1096 ? SLl Jul24 0:00 > /usr/sbin/xenconsoled --pid-file=/var/run/xenconsoled.pid --log=guest >> >> I must admit, I never have it straight in my head about hvc0 vs xvc0, etc. > earlyprintk=xen doesn''t seem to have made any difference. >> >> I am wondering if I did something wrong at compile time (it has been known) > > If with a known good domain you don''t get anything > under /var/log/xen/consoles/ then I don''t know what is going on. > > With any modern kernel console=hvc0 is what you want, if your kernel is > old but not a complete relic then "console=hvc0 xencons=hvc" should > work.Anything new is PVOPS Ubuntu kernel 3.2 onwards and I have some CentOS 5 DomU''s using the original Xen kernel that comes with it. Thanks for the tip.> >> > >> > Once you are sure of that then you ought to get *something* out of the >> > crashing guest console -- if not then you might try adding >> > "earlyprintk=xen" to the guest kernel command line. >> > >> >> I can''t help feeling there is a longstanding problem with > 12.04 Ubuntu >> >> Xen install files. I tried 64 bit and 32 bits version, same > behaviour. >> > >> > If you think it might be an Ubuntu bug then trawling Launchpad might > be >> > worthwhile. Nothing springs to my mind but that doesn''t really > mean >> > much. >> > >> >> I re-read the other thread and the other guy had exactly the > same >> >> problem but resolved it by using some Ubuntu Xen creation tool. > He was >> >> using Xen 4.2.1 >> > >> > Depending on what "some Ubuntu Xen creation tool" is it may > well be >> > using some different kernel or something. >> >> He succesfully created it using >> >> >> xen-create-image --hostname=ubuntu \ >> --memory=512mb \ >> --vcpus=2 \ >> --lvm=center \ >> --dhcp \ >> --pygrub \ >> --dist=precise >> >> I''ve never used this tool and I prefer to do things distribution > agnostically as I have Xen on Ubuntu and Scientific Linux 6.4 > > Right. The approach above is bascially debbootstrap + using the dom0 > kernel (which you can be reasonably sure is correct). > > One experiment you could try is to extract the kernel from your guest > image and try booting it via the "dom0 path" method.The set-up Ubuntu Xen install is encapsulated within a kernel and a ram drive image, so there is no extracting to be done (assuming I understand you correctly). Having said that, your suggestion did give me an idea to try the 13.04 kernel with the 12.04 ram drive. It was a fair guess that the kernel should be functionally similar and the meat and potatoes of the installer were in the ram drive image. As luck would have it, this seems to work a treat and I managed to set-up a working 12.04 domU this way, which was the aim. So, mystery not solved, but at least I have a work-around. I''ll re-test this against Xen 4.3, just for completeness. Thanks again for your help.> > > Ian. > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xen.org > http://lists.xen.org/xen-users >
Ian Campbell
2013-Aug-02 15:57 UTC
Re: Trying to create new domain on 4.3 but domU is starting crashed (-sc-)
On Thu, 2013-08-01 at 17:04 +0100, Ian Murray wrote:> > With any modern kernel console=hvc0 is what you want, if your kernel is > > old but not a complete relic then "console=hvc0 xencons=hvc" should > > work. > > Anything new is PVOPS Ubuntu kernel 3.2 onwards and I have some CentOS > 5 DomU''s using the original Xen kernel that comes with it.Actually pvops (and therefore console=hvc0) 32-bit first landed around about 2.6.24 and 64-bit around 2.6.27, 2.6.32 was when it really became ready for normal domU users though IMHO. Around the time pvops was introduced the "hvc" name and the xenconscommand line to select the name were added to the classic-kernels too, including, I thought, the CentOS5 ones (in new enough point releases). Maybe I''m mistaken about that latter point though. There were also forward ported classic-Xen kernels which overlapped with the pvops stuff, and those would know about xencons too. Since newer kernels will use hvc0 by default and don''t know about (and therefore ignore) xencons= and most older kernels & newer forward ported classic-Xen kernels understand xencons using "console=hvc0 xencons=hvc" should work just about everywhere except for the most ancient distro kernels (pre 2.6.18 level stuff, unless I''m wrong about CentOS5). Ian.