<div><div dir="auto">Hello,</div><div><br><div class="gmail_quote"></div></div></div><div><div dir="ltr" class="gmail_attr">On Wed, 21 Apr 2021 at 13:29, <<a href="mailto:fatcharly@gmx.de" target="_blank">fatcharly@gmx.de</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi,<br>
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I'm using a drbd 9.13 on CentOS 8 with pacemaker for a mysql-cluster. This cluster is running on a kvm/qemu cluster.</blockquote><div dir="auto"><br></div></div><div><div dir="auto">You are probably referring to the drbd-utils version as the most current drbd kernel module version is drbd-9.0.28.</div></div><div dir="auto"><br></div><div dir="auto"><br></div><div><div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex" dir="auto">The virtual harddisks for the virtual mysql-nodes are qcow2 devices.<br>
Is this really a good idea to use qcow2 as base for drbd ?</blockquote><div dir="auto"><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex" dir="auto"></blockquote><div dir="auto"><br></div><div dir="auto">Since drbd is a block device I would not use qcow2 on top of it, mainly for performance purposes.I'd rather deploy the VMs directly onto it (raw).</div><div dir="auto"><br></div><div dir="auto"><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex" dir="auto">I can see that the qcow2-devices have grown larger as the drives of the virtual machines really are right now. Is this normal ?</blockquote><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">Do you mean that the size of the qcow2 on the host has grown up larger than the actual "used" size withing the guest? If yes, then I think that's a case of correctly configuring the trim or discard support both on the guest and the host (not related to drbd).</div><div dir="auto"><br></div><div dir="auto">Yanni</div></div></div>
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