Maximum time node can be offline.
Hello all, Is there a maximum length of time an Ovirt Node 4.2 based host can be offline in a cluster before it would have issues when powered back on? The reason I ask is in my lab I currently have a three node cluster that works really well, however a lot of the time I only actually need the resources of one host, so to save power I'd like to keep the other two offline until needed. I can always script them to boot once a week or so if I need to. Thanks, Thomas
--_000_151808472464571365leedsbeckettacuk_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello, you should be able to use the power saving cluster scheduling po= licy. https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.2-be= ta/html/administration_guide/sect-Scheduling_Policies Regards, Paul S. ________________________________ From: users-bounces@ovirt.org <users-bounces@ovirt.org> on behalf of Thomas= Letherby <xrs444@xrs444.net> Sent: 08 February 2018 05:51 To: users@ovirt.org Subject: [ovirt-users] Maximum time node can be offline. Hello all, Is there a maximum length of time an Ovirt Node 4.2 based host can be offli= ne in a cluster before it would have issues when powered back on? The reason I ask is in my lab I currently have a three node cluster that wo= rks really well, however a lot of the time I only actually need the resourc= es of one host, so to save power I'd like to keep the other two offline unt= il needed. I can always script them to boot once a week or so if I need to. Thanks, Thomas To view the terms under which this email is distributed, please go to:- http://disclaimer.leedsbeckett.ac.uk/disclaimer/disclaimer.html --_000_151808472464571365leedsbeckettacuk_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <html> <head> <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Diso-8859-= 1"> <style type=3D"text/css" style=3D"display:none"><!--P{margin-top:0;margin-b= ottom:0;} --></style> </head> <body dir=3D"ltr" style=3D"font-size:12pt;color:#000000;background-color:#F= FFFFF;font-family:Calibri,Arial,Helvetica,sans-serif;"> <p>Hello,</p> <p> you should be able to use the p= ower saving cluster scheduling policy.</p> <p><br> </p> <p><a href=3D"https://access.redhat.com/documentation/en-us/red_hat_virtual= ization/4.2-beta/html/administration_guide/sect-Scheduling_Policies">https:= //access.redhat.com/documentation/en-us/red_hat_virtualization/4.2-beta/htm= l/administration_guide/sect-Scheduling_Policies</a></p> <p><br> </p> <p>Regards,</p> <p> Paul S.<br> </p> <div style=3D"color: rgb(33, 33, 33);"> <hr tabindex=3D"-1" style=3D"display:inline-block; width:98%"> <div id=3D"divRplyFwdMsg" dir=3D"ltr"><font style=3D"font-size:11pt" face= =3D"Calibri, sans-serif" color=3D"#000000"><b>From:</b> users-bounces@ovirt= .org <users-bounces@ovirt.org> on behalf of Thomas Letherby <xrs44= 4@xrs444.net><br> <b>Sent:</b> 08 February 2018 05:51<br> <b>To:</b> users@ovirt.org<br> <b>Subject:</b> [ovirt-users] Maximum time node can be offline.</font> <div> </div> </div> <div> <div dir=3D"ltr">Hello all, <div><br> </div> <div>Is there a maximum length of time an Ovirt Node 4.2 based host can be = offline in a cluster before it would have issues when powered back on?</div=
<div><br> </div> <div>The reason I ask is in my lab I currently have a three node cluster th= at works really well, however a lot of the time I only actually need the re= sources of one host, so to save power I'd like to keep the other two offlin= e until needed.</div> <div><br> </div> <div>I can always script them to boot once a week or so if I need to.</div> <div><br> </div> <div>Thanks,</div> <div><br> </div> <div>Thomas</div> </div> </div> </div> To view the terms under which this email is distributed, please go to:- <br=
<a href=3D"http://disclaimer.leedsbeckett.ac.uk/disclaimer/disclaimer.html"= target=3D"_blank">http://disclaimer.leedsbeckett.ac.uk/disclaimer/disclaim= er.html</a> <p></p> </body> </html> --_000_151808472464571365leedsbeckettacuk_--
Thanks, that answers my follow up question! :) My concern is that I could have a host off-line for a month say, is that going to cause any issues? Thanks, Thomas On Thu, Feb 8, 2018 at 3:12 AM Staniforth, Paul < P.Staniforth@leedsbeckett.ac.uk> wrote:
Hello,
you should be able to use the power saving cluster scheduling policy.
https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.2-bet...
Regards,
Paul S. ------------------------------ *From:* users-bounces@ovirt.org <users-bounces@ovirt.org> on behalf of Thomas Letherby <xrs444@xrs444.net> *Sent:* 08 February 2018 05:51 *To:* users@ovirt.org *Subject:* [ovirt-users] Maximum time node can be offline.
Hello all,
Is there a maximum length of time an Ovirt Node 4.2 based host can be offline in a cluster before it would have issues when powered back on?
The reason I ask is in my lab I currently have a three node cluster that works really well, however a lot of the time I only actually need the resources of one host, so to save power I'd like to keep the other two offline until needed.
I can always script them to boot once a week or so if I need to.
Thanks,
Thomas To view the terms under which this email is distributed, please go to:- http://disclaimer.leedsbeckett.ac.uk/disclaimer/disclaimer.html
On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <xrs444@xrs444.net> wrote:
Thanks, that answers my follow up question! :)
My concern is that I could have a host off-line for a month say, is that going to cause any issues?
Thanks,
Thomas
I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you thinking about any particular scenario?
Hi, the hosts are almost stateless and we set up most of what is needed during activation. Hosted engine has some configuration stored locally, but that is just the path to the storage domain. I think you should be fine unless you change the network topology significantly. I would also install security updates once in while. We can even shut down the hosts for you when you configure two cluster scheduling properties: EnableAutomaticPM and HostsInReserve. HostsInReserve should be at least 1 though. It behaves like this, as long as the reserve host is empty, we shut down all the other empty hosts. And we boot another host once a VM does not fit on other used hosts and is places on the running reserve host. That would save you the power of just one host, but it would still be highly available (if hosted engine and storage allows that too). Bear in mind that single host cluster is not highly available at all. Best regards Martin Sivak On Fri, Feb 9, 2018 at 8:25 AM, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote:
On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <xrs444@xrs444.net> wrote:
Thanks, that answers my follow up question! :)
My concern is that I could have a host off-line for a month say, is that going to cause any issues?
Thanks,
Thomas
I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you thinking about any particular scenario?
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
That's exactly what I needed to know, thanks all. I'll schedule a script for the nodes to reboot and patch once every week or two and then I can let it run without me needing to worry about it. Thomas On Fri, Feb 9, 2018, 2:26 AM Martin Sivak <msivak@redhat.com> wrote:
Hi,
the hosts are almost stateless and we set up most of what is needed during activation. Hosted engine has some configuration stored locally, but that is just the path to the storage domain.
I think you should be fine unless you change the network topology significantly. I would also install security updates once in while.
We can even shut down the hosts for you when you configure two cluster scheduling properties: EnableAutomaticPM and HostsInReserve. HostsInReserve should be at least 1 though. It behaves like this, as long as the reserve host is empty, we shut down all the other empty hosts. And we boot another host once a VM does not fit on other used hosts and is places on the running reserve host. That would save you the power of just one host, but it would still be highly available (if hosted engine and storage allows that too).
Bear in mind that single host cluster is not highly available at all.
Best regards
Martin Sivak
On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <xrs444@xrs444.net> wrote:
Thanks, that answers my follow up question! :)
My concern is that I could have a host off-line for a month say, is that going to cause any issues?
Thanks,
Thomas
I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you
On Fri, Feb 9, 2018 at 8:25 AM, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote: thinking
about any particular scenario?
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
On Sat, Feb 10, 2018 at 5:47 PM, Thomas Letherby <xrs444@xrs444.net> wrote:
That's exactly what I needed to know, thanks all.
I'll schedule a script for the nodes to reboot and patch once every week or two and then I can let it run without me needing to worry about it.
An example on how to check for updates is available @ https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/upgrade_h... Y.
Thomas
On Fri, Feb 9, 2018, 2:26 AM Martin Sivak <msivak@redhat.com> wrote:
Hi,
the hosts are almost stateless and we set up most of what is needed during activation. Hosted engine has some configuration stored locally, but that is just the path to the storage domain.
I think you should be fine unless you change the network topology significantly. I would also install security updates once in while.
We can even shut down the hosts for you when you configure two cluster scheduling properties: EnableAutomaticPM and HostsInReserve. HostsInReserve should be at least 1 though. It behaves like this, as long as the reserve host is empty, we shut down all the other empty hosts. And we boot another host once a VM does not fit on other used hosts and is places on the running reserve host. That would save you the power of just one host, but it would still be highly available (if hosted engine and storage allows that too).
Bear in mind that single host cluster is not highly available at all.
Best regards
Martin Sivak
On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <xrs444@xrs444.net> wrote:
Thanks, that answers my follow up question! :)
My concern is that I could have a host off-line for a month say, is
going to cause any issues?
Thanks,
Thomas
I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you
On Fri, Feb 9, 2018 at 8:25 AM, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote: that thinking
about any particular scenario?
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Thanks Yaniv, that looks like a perfect starting point! Thomas On Sun, Feb 11, 2018, 1:36 AM Yaniv Kaul <ykaul@redhat.com> wrote:
On Sat, Feb 10, 2018 at 5:47 PM, Thomas Letherby <xrs444@xrs444.net> wrote:
That's exactly what I needed to know, thanks all.
I'll schedule a script for the nodes to reboot and patch once every week or two and then I can let it run without me needing to worry about it.
An example on how to check for updates is available @ https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/upgrade_h... Y.
Thomas
On Fri, Feb 9, 2018, 2:26 AM Martin Sivak <msivak@redhat.com> wrote:
Hi,
the hosts are almost stateless and we set up most of what is needed during activation. Hosted engine has some configuration stored locally, but that is just the path to the storage domain.
I think you should be fine unless you change the network topology significantly. I would also install security updates once in while.
We can even shut down the hosts for you when you configure two cluster scheduling properties: EnableAutomaticPM and HostsInReserve. HostsInReserve should be at least 1 though. It behaves like this, as long as the reserve host is empty, we shut down all the other empty hosts. And we boot another host once a VM does not fit on other used hosts and is places on the running reserve host. That would save you the power of just one host, but it would still be highly available (if hosted engine and storage allows that too).
Bear in mind that single host cluster is not highly available at all.
Best regards
Martin Sivak
On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <xrs444@xrs444.net> wrote:
Thanks, that answers my follow up question! :)
My concern is that I could have a host off-line for a month say, is
going to cause any issues?
Thanks,
Thomas
I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you
On Fri, Feb 9, 2018 at 8:25 AM, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote: that thinking
about any particular scenario?
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
This is a multi-part message in MIME format. --------------345D358126844660EA6D498E Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit On 02/10/2018 05:47 PM, Thomas Letherby wrote:
That's exactly what I needed to know, thanks all.
I'll schedule a script for the nodes to reboot and patch once every week or two and then I can let it run without me needing to worry about it.
Is this shell or python script with connection to oVirt engine? My 4.2 node don't shutdown properly until I'm shutdown all VMs take it into maintenance mode manually. Shutdown process freezes at certain point.
Thomas
On Fri, Feb 9, 2018, 2:26 AM Martin Sivak <msivak@redhat.com> wrote:
Hi,
the hosts are almost stateless and we set up most of what is needed during activation. Hosted engine has some configuration stored locally, but that is just the path to the storage domain.
I think you should be fine unless you change the network topology significantly. I would also install security updates once in while.
We can even shut down the hosts for you when you configure two cluster scheduling properties: EnableAutomaticPM and HostsInReserve. HostsInReserve should be at least 1 though. It behaves like this, as long as the reserve host is empty, we shut down all the other empty hosts. And we boot another host once a VM does not fit on other used hosts and is places on the running reserve host. That would save you the power of just one host, but it would still be highly available (if hosted engine and storage allows that too).
Bear in mind that single host cluster is not highly available at all.
Best regards
Martin Sivak
On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <xrs444@xrs444.net> wrote:
Thanks, that answers my follow up question! :)
My concern is that I could have a host off-line for a month say, is that going to cause any issues?
Thanks,
Thomas
I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you
On Fri, Feb 9, 2018 at 8:25 AM, Gianluca Cecchi <gianluca.cecchi@gmail.com> wrote: thinking
about any particular scenario?
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
--------------345D358126844660EA6D498E Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 7bit <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body text="#000000" bgcolor="#FFFFFF"> <div class="moz-cite-prefix">On 02/10/2018 05:47 PM, Thomas Letherby wrote:<br> </div> <blockquote type="cite" cite="mid:CAEOgKtwD2LHgCA7sbe969gG4zUp9ZQ3SeiS2atTmztBMTxn-eA@mail.gmail.com"> <pre wrap="">That's exactly what I needed to know, thanks all. I'll schedule a script for the nodes to reboot and patch once every week or two and then I can let it run without me needing to worry about it.</pre> </blockquote> <br> Is this shell or python script with connection to oVirt engine? My 4.2 node don't shutdown properly until I'm shutdown all VMs take it into maintenance mode manually. Shutdown process freezes at certain point.<br> <br> <blockquote type="cite" cite="mid:CAEOgKtwD2LHgCA7sbe969gG4zUp9ZQ3SeiS2atTmztBMTxn-eA@mail.gmail.com"> <pre wrap=""> Thomas On Fri, Feb 9, 2018, 2:26 AM Martin Sivak <a class="moz-txt-link-rfc2396E" href="mailto:msivak@redhat.com"><msivak@redhat.com></a> wrote: </pre> <blockquote type="cite"> <pre wrap="">Hi, the hosts are almost stateless and we set up most of what is needed during activation. Hosted engine has some configuration stored locally, but that is just the path to the storage domain. I think you should be fine unless you change the network topology significantly. I would also install security updates once in while. We can even shut down the hosts for you when you configure two cluster scheduling properties: EnableAutomaticPM and HostsInReserve. HostsInReserve should be at least 1 though. It behaves like this, as long as the reserve host is empty, we shut down all the other empty hosts. And we boot another host once a VM does not fit on other used hosts and is places on the running reserve host. That would save you the power of just one host, but it would still be highly available (if hosted engine and storage allows that too). Bear in mind that single host cluster is not highly available at all. Best regards Martin Sivak On Fri, Feb 9, 2018 at 8:25 AM, Gianluca Cecchi <a class="moz-txt-link-rfc2396E" href="mailto:gianluca.cecchi@gmail.com"><gianluca.cecchi@gmail.com></a> wrote: </pre> <blockquote type="cite"> <pre wrap="">On Fri, Feb 9, 2018 at 2:30 AM, Thomas Letherby <a class="moz-txt-link-rfc2396E" href="mailto:xrs444@xrs444.net"><xrs444@xrs444.net></a> </pre> </blockquote> <pre wrap="">wrote: </pre> <blockquote type="cite"> <blockquote type="cite"> <pre wrap=""> Thanks, that answers my follow up question! :) My concern is that I could have a host off-line for a month say, is that going to cause any issues? Thanks, Thomas </pre> </blockquote> <pre wrap=""> I think that if in the mean time you don't make any configuration changes and you don't update anything, there is no reason to have problems. In case of changes done, it could depend on what they are: are you </pre> </blockquote> <pre wrap="">thinking </pre> <blockquote type="cite"> <pre wrap="">about any particular scenario? _______________________________________________ Users mailing list <a class="moz-txt-link-abbreviated" href="mailto:Users@ovirt.org">Users@ovirt.org</a> <a class="moz-txt-link-freetext" href="http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.org/mailman/listinfo/users</a> </pre> </blockquote> <pre wrap=""> </pre> </blockquote> <pre wrap=""> </pre> <br> <fieldset class="mimeAttachmentHeader"></fieldset> <br> <pre wrap="">_______________________________________________ Users mailing list <a class="moz-txt-link-abbreviated" href="mailto:Users@ovirt.org">Users@ovirt.org</a> <a class="moz-txt-link-freetext" href="http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.org/mailman/listinfo/users</a> </pre> </blockquote> <p><br> </p> </body> </html> --------------345D358126844660EA6D498E--
participants (6)
-
Andrei V -
Gianluca Cecchi -
Martin Sivak -
Staniforth, Paul -
Thomas Letherby -
Yaniv Kaul