<div dir="ltr"><br><div> Thanks!</div><div><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Apr 15, 2021 at 1:08 AM Andreas Dilger <<a href="mailto:adilger@whamcloud.com">adilger@whamcloud.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Apr 15, 2021, at 00:52, Åke Sandgren <<a href="mailto:ake.sandgren@hpc2n.umu.se" target="_blank">ake.sandgren@hpc2n.umu.se</a>> wrote:<br>
> <br>
> \ufeff<br>
> <br>
>> On 4/15/21 5:12 AM, Andreas Dilger via lustre-discuss wrote:<br>
>> On Apr 14, 2021, at 18:42, Bill Anderson via lustre-discuss<br>
>> <<a href="mailto:lustre-discuss@lists.lustre.org" target="_blank">lustre-discuss@lists.lustre.org</a><br>
>> <mailto:<a href="mailto:lustre-discuss@lists.lustre.org" target="_blank">lustre-discuss@lists.lustre.org</a>>> wrote:<br>
>>> <br>
>>> <br>
>>> Hi All,<br>
>>> <br>
>>> I'm trying to figure out how to migrate files stored on an OST to<br>
>>> an MDT (that's using DoM) and to migrate files stored on an MDT to an<br>
>>> OST (e.g., if the MDT is getting full). I can see how to migrate<br>
>>> between OSTs, but not between OSTs and MDTs. I'm running Lustre 2.12.3.<br>
>>> <br>
>>> Do you happen to know the syntax for migration between OSTs and MDTs?<br>
>>> <br>
>>> Thanks for any help!<br>
>> <br>
>> You just use "lfs migrate <file layout> <file>" to migrate from DoM<br>
>> files to OST objects. However, OST-to-DoM migration isn't available<br>
>> until 2.13.<br>
> <br>
> Couldn't you just use lfs mirror extend with a PFL that points into the<br>
> DoM, and then a resync/split<br>
<br>
Yes, and that's what happens in 2.13 when this functionality is<br>
implemented. To migrate from DoM->OST you can just make a copy of<br>
the file and swap layouts. The issue in 2.12 is that you can't write into the<br>
MDT inode to do OST->DoM migration/mirroring. <br>
<br>
Cheers, Andreas</blockquote></div>