From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takahiro Yasui Date: Mon, 22 Feb 2010 04:18:35 -0500 Subject: [PATCH 0 of 13] LVM add 'mirrored' log type In-Reply-To: References: <1266429310.29358.35.camel@hydrogen.msp.redhat.com> Message-ID: <4B824BEB.60708@redhat.com> List-Id: To: lvm-devel@redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Jonathan Brassow wrote: > I'm also testing the other approach; that is, allowing lvconvert to take > non-top-level LVs (e.g. "lv_mlog"). It seems to work just fine. We > might want to strongly consider allowing this. > > There are drawbacks to this approach too, however. For example, when > one of the devices of the log fails, it will be treated as an 'image' > failure, and not a 'log' failure (I can fix that though by checking its > lv->status). If we decide to go this route, we will have to decide if > this is the behavior we want or not. (Once the log is linear, it will > behave as you would expect - either being replaced or removed according > to the log policy.) This approach requires two threads in dmeventd; it is for a top-level LV, and another is for a mirrored log. If a leg and mirrored log failed at the same time, a mirrored log needs to be recovered before a top-level LV. I think this approach is also good if we can handle this situation. Thanks, Taka