Xen users - Oct 2007 - Error: (9, ''Bad file descriptor'')

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

I also created a fresh domU using the wiki article located at
http://wiki.centos.org/HowTos/Xen/InstallingCentOSDomU

After this since i have to use lvm, i created a new lvm volume, mounted the
file, copied the first partition contents to the lvm volume. Now when i try
to boot the lvm volume, it gives me the below error

mount: could not find filesystem
''/dev/root''
> Setting up other filesystems.
> Setting up new root fs
> setuproot: moving /dev failed: No such file or directory
> no fstab.sys, mounting internal defaults
> setuproot: error mounting /proc: No such file or directory
> setuproot: error mounting /sys: No such file or directory
> Switching to new root and running init.
> unmounting old /dev
> unmounting old /proc
> unmounting old /sys
> switchroot: mount failed: No such file or directory
> Kernel panic - not syncing: Attempted to kill init!
>
Here is the config file

name = "new2"
memory = "512"
disk = [ ''phy:/dev/VolGroup00/new2,xvda1,w'',]
vif = [ ''bridge=xenbr0'', ]
bootloader="/usr/bin/pygrub"
vcpus=7
extra="single"
on_reboot = ''restart''
on_crash = ''restart''

In the above i tried both xvda and xvda1, they give the same error.

/etc/fstab inside the lvm volume

/dev/xvda1              /                       ext3    defaults        1 1
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
tmpfs                   /dev/shm                tmpfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
sysfs                   /sys                    sysfs   defaults        0 0


Any pointers / ideas on how to fix the problems will be appreciated.

-- 
regards,

Anand Gupta

Hmm.. somehow i am getting this now. Haven''t changed any config of xen,
and
i am in /root, so why it should show that message.

xm list
Error: (9, ''Bad file descriptor'')
Usage: xm list [options] [Domain, ...]

List information about all/some domains.
  -l, --long                     Output all VM details in SXP
  --label                        Include security labels
  --state=<state>                Select only VMs with the specified state


-- 
regards,

Anand Gupta

Just did a reinstall of xen by running install.sh inside dist directory, and
rebooted dom0, things turned back to normal

xm list
Name                                        ID   Mem VCPUs      State
Time(s)
Domain-0                                     0  3011     8     r-----
134.9

Strange, but must be something i did... Now if the other problem can get
resolved, i can put this box aside and concentrate on other servers :p

On 11/1/07, Anand Gupta <xen.mails@gmail.com>
wrote:
>
> Hmm.. somehow i am getting this now. Haven''t changed any config of
xen,
> and i am in /root, so why it should show that message.
>
> xm list
> Error: (9, ''Bad file descriptor'')
> Usage: xm list [options] [Domain, ...]
>
> List information about all/some domains.
>   -l, --long                     Output all VM details in
> SXP
>   --label                        Include security
> labels
>   --state=<state>                Select only VMs with the specified
> state
>
>
> --
> regards,
>
> Anand Gupta



-- 
regards,

Anand Gupta