Bug#923646: debian-installer: iSCSI partitions not marked as _netdev in /etc/fstab

[Heinrich Schuchardt <xypron.debian@gmx.de>]

Package: debian-installer
Version: 20190302-5
Severity: normal

Dear Maintainer,

I used
https://cdimage.debian.org/cdimage/daily-builds/daily/20190302-5/arm64/iso-cd/debian-testing-arm64-netinst.iso
to install Debian Buster on a Pine A64 LTS board.

My complete Debian installation is on an iSCSI target. So for booting I
use U-Boot to start iPXE (snp.efi), which loads grubaa64.efi from the
iSCSI target.

As I am booting from an iSCSI target the reboot sequence must be:
- unmount all drives
- logoff iSCSI target
- shutdown network

Unfortunately when I tried to reboot the board started hanging in a loop
trying to raise network interfaces.

The fix was to add the option _netdev to all iSCSI mounts in /etc/fstab:

UUID=.. / ext4 _netdev,errors=remount-ro 0 1
UUID=.. /boot ext2 _netdev,nofail,noatime,nodiratime 0 2
UUID=.. /boot/efi  vfat _netdev,nofail 0 2
UUID=.. /home ext4 _netdev,nofail,noatime,nodiratime 0 2
tmpfs /tmp tmpfs nosuid 0 0
/dev/sr0 /media/cdrom0 udf,iso9660 user,noauto 0 0

Please, change the installer scripts such that iSCSI partitions
automatically receive the _netdev attribute in /etc/fstab.

Best regards

Heinrich Schuchardt