Hey, If you use Stretch or beyond as the NFSROOT to build anything less than Ubuntu 16.10 with ext4 filesystems, then those filesystems can't be fsck'ed on the resulting system.
Because of this I've had to keep a Jessie NFSROOT around to build those systems. But I finally encountered a system which can't be built by Jessie with my FAI Profile [0]. However, there is a fix! This assumes that you mount an NFSROOT using aufs or overlayfs so any modifications are transient. Use a hook to modify /etc/mke2fs.conf if building affected systems. In my case I create a class called UBUNTU or Ubuntu machines, so I created hooks/partition.UBUNTU with the following content: -- Begin -- #!/bin/bash # Trusty and Xenial can't fsck ext4 filesystems with the metadata_csum # flag. # See: https://bugs.launchpad.net/ubuntu/+source/e2fsprogs/+bug/1601997 ifclass -o XENIAL TRUSTY \ && sed -i 's/,metadata_csum//' /etc/mke2fs.conf -- End -- Cheers, Andrew [0] I run lspci during the build to identify PCI cards which need customised actions, and a new server uses 32 byte PCI IDs which lspci on Jessie doesn't support. -- Andrew Ruthven, Wellington, New Zealand and...@etc.gen.nz | linux.conf.au 2020, Gold Coast, AU https://catalystcloud.nz | https://lca2020.linux.org.au