FAI with nfsroot on stretch failing with read-only error at /tmp/fai

[Nat Sincheler]

We are able to PXE boot and do an NFS mount, but we are getting a 
"Read-only file system" error when FAI is trying to make the directory 
/tmp/fai.

We get to the point where we see this at the console:

INIT: version 2.88 booting
cat: /sys/class/net/eth0/name_assign_type: Invalid argument
cat: /sys/class/net/eth0/name_assign_type: Invalid argument
[    35.498423] dracut: Switching root
mkdir: cannot create directory '/tmp/fai': Read-only file system
chown: cannot access 'tmp/fai': No such file or directory


A screen-shot of the console shows the error:
https://drive.google.com/file/d/0B6Uk8YXuZvLJb1Q0eGNPVDBva3c/view?usp=sharing


Any ideas?