Hi all, I''m running 2 domUs simulataneously with multiple img partitions mounted. On starting the 3rd I got the following error: Using config file "/etc/xen/conf/gust3.cfg". Error: Device 769 (vbd) could not be connected. Failed to find an unused loop device. I found this solution: you could pass it as an option to your kernel at boot time, if you use grub, add "max_loop=64" at the end of your kernel line, then *reboot* the server and look how much devices are declared in /dev/loop* As you can see it requires to reboot the server which is not possible since it is a production server : Can someone please give me a proposal to increase loop devices without rebooting the server ? Thanks in advance, -- Yassine AYACHI Ingénieur réseaux et systèmes _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Mon, Apr 11, 2011 at 4:29 PM, yassine ayachi <ayachi.yassine@gmail.com> wrote:> you could pass it as an option to your kernel at boot time, if you use grub, > add "max_loop=64" at the end of your kernel line, then reboot the server > and look how much devices are declared in /dev/loop*IIRC it should be loop.max_loop=64 when on kernel line> > As you can see it requires to reboot the server which is not possible since > it is a production server : > > Can someone please give me a proposal to increase loop devices without > rebooting the server ?Not possible. ... alhtough depending on the version of Xen you use, you can try using "tap:aio:/" instead of "file:/" on your domU config file. -- Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Mon, Apr 11, 2011 at 11:37 AM, Fajar A. Nugraha <list@fajar.net> wrote:> On Mon, Apr 11, 2011 at 4:29 PM, yassine ayachi > <ayachi.yassine@gmail.com> wrote: >> you could pass it as an option to your kernel at boot time, if you use grub, >> add "max_loop=64" at the end of your kernel line, then reboot the server >> and look how much devices are declared in /dev/loop* > > IIRC it should be loop.max_loop=64 when on kernel line > >> >> As you can see it requires to reboot the server which is not possible since >> it is a production server : >> >> Can someone please give me a proposal to increase loop devices without >> rebooting the server ? > > Not possible. > > ... alhtough depending on the version of Xen you use, you can try > using "tap:aio:/" instead of "file:/" on your domU config file. > > -- > Fajar > > _______________________________________________Is it not maybe possible to change this value with ksplice, and thus not have to reboot? -- Kind Regards Rudi Ahlers SoftDux Website: http://www.SoftDux.com Technical Blog: http://Blog.SoftDux.com Office: 087 805 9573 Cell: 082 554 7532 _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Mon, Apr 11, 2011 at 12:43 PM, Rudi Ahlers <Rudi@softdux.com> wrote:> On Mon, Apr 11, 2011 at 11:37 AM, Fajar A. Nugraha <list@fajar.net> wrote: >> On Mon, Apr 11, 2011 at 4:29 PM, yassine ayachi >> <ayachi.yassine@gmail.com> wrote: >>> you could pass it as an option to your kernel at boot time, if you use grub, >>> add "max_loop=64" at the end of your kernel line, then reboot the server >>> and look how much devices are declared in /dev/loop* >> >> IIRC it should be loop.max_loop=64 when on kernel line >> >>> >>> As you can see it requires to reboot the server which is not possible since >>> it is a production server : >>> >>> Can someone please give me a proposal to increase loop devices without >>> rebooting the server ? >> >> Not possible. >> >> ... alhtough depending on the version of Xen you use, you can try >> using "tap:aio:/" instead of "file:/" on your domU config file. >> >> -- >> Fajar >> >> _______________________________________________ > > > > Is it not maybe possible to change this value with ksplice, and thus > not have to reboot? > > >You could manually create the loop devices. They have major number 7 mknod -m660 /dev/loopX b 7 X && chown root:disk /dev/loopX Replace X with the numbers that continue your existing loop devices. For example, if you have /dev/loop0 through /dev/loop7, you could create /dev/loop8 and so forth by issuing mknod -m660 /dev/loop8 b 7 8 && chown root:disk /dev/loop8 mknod -m660 /dev/loop9 b 7 9 && chown root:disk /dev/loop9 You might want to script the creation if you plan to create many additional loop devices via a for loop. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi Claudiu, Thank you very much, your solution is safe and worked for me just fine, PS. I just noticed that the best way to shutdown a domU is to do "xm shutdown" instead of "xm destroy" for the loop devices to be properly unmounted and reused, thanks to those who responded, 2011/4/11 Claudiu Curcă <alexstrasza2@gmail.com>> On Mon, Apr 11, 2011 at 12:43 PM, Rudi Ahlers <Rudi@softdux.com> wrote: > > On Mon, Apr 11, 2011 at 11:37 AM, Fajar A. Nugraha <list@fajar.net> > wrote: > >> On Mon, Apr 11, 2011 at 4:29 PM, yassine ayachi > >> <ayachi.yassine@gmail.com> wrote: > >>> you could pass it as an option to your kernel at boot time, if you use > grub, > >>> add "max_loop=64" at the end of your kernel line, then reboot the > server > >>> and look how much devices are declared in /dev/loop* > >> > >> IIRC it should be loop.max_loop=64 when on kernel line > >> > >>> > >>> As you can see it requires to reboot the server which is not possible > since > >>> it is a production server : > >>> > >>> Can someone please give me a proposal to increase loop devices without > >>> rebooting the server ? > >> > >> Not possible. > >> > >> ... alhtough depending on the version of Xen you use, you can try > >> using "tap:aio:/" instead of "file:/" on your domU config file. > >> > >> -- > >> Fajar > >> > >> _______________________________________________ > > > > > > > > Is it not maybe possible to change this value with ksplice, and thus > > not have to reboot? > > > > > > > You could manually create the loop devices. They have major number 7 > > mknod -m660 /dev/loopX b 7 X && chown root:disk /dev/loopX > > Replace X with the numbers that continue your existing loop devices. > > For example, if you have /dev/loop0 through /dev/loop7, you could > create /dev/loop8 and so forth by issuing > > mknod -m660 /dev/loop8 b 7 8 && chown root:disk /dev/loop8 > mknod -m660 /dev/loop9 b 7 9 && chown root:disk /dev/loop9 > > You might want to script the creation if you plan to create many > additional loop devices via a for loop. >-- Yassine AYACHI Ingénieur réseaux et systèmes _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users