>> I read below words on the report of <KVM Live Migration: Weather >> forecast (May 29, 2013)>, We were going to remove the old >> block-migration code Then people fixed it >> Good: it works now >> Bad: We have to maintain both >> It uses the same port than migration >> You need to migrate all/none of block devices >> >> The old block-migration code said above is that in block-migration.c? > >Yes. > >> What are the reasons of removing the old block-migration code? Buggy >> implementation? Or need to migrate all/none of block devices? > >Buggy and tightly coupled with the live migration code, making it hard to >modify either area independently.
Thanks a lot for explaining. Till now, we still use the old block-migration code in our virtualization solution. Could you detail the bugs that the old block-migration code have? Thanks, Zhang Haoyu > >> What's the substitutional method? drive_mirror? > >drive_mirror over NBD is an alternative. There are security and integration >challenges with those approaches but libvirt has added drive-mirror block >migration support. > >Stefan