is there a reason CentOS uses such an old kernel?
The server went live two years ago.
Without doing an actual search, it seems like this “my install broke because of devicemapper” topic comes up three times a week. (And I think I remember some post somewhere that says “we recently fixed the test to see if people were using this likely-broken thing, so we let some people install with the thing we think is broken”). This is among the most cogent responses I’ve seen. Perhaps there should be a #HOWTO about this issue that we could just point people to?
It’s probably not too soon to upgrade the kernel, then.
Closing this topic as out of date.
overlay2 is now the recommended storage driver for current versions of Docker. From the Docker documentation as of 2019-06-19T04:00:00Z, emphasis mine:
overlay2is the preferred storage driver, for all currently supported Linux distributions, and requires no extra configuration.
aufsis the preferred storage driver for Docker 18.06 and older, when running on Ubuntu 14.04 on kernel 3.13 which has no support for
devicemapperis supported, but requires
direct-lvmfor production environments, because
loopback-lvm, while zero-configuration, has very poor performance.
devicemapperwas the recommended storage driver for CentOS and RHEL, as their kernel version did not support
overlay2. However, current versions of CentOS and RHEL now have support for
overlay2, which is now the recommended driver.