Created attachment 1100580 [details]
Report generated by dracut

Description of problem:
We have a diskless setup where we boot client machines via PXE-boot 
with the Fedora root filesystem provided read-only via iSCSI. 
During PXE-boot, the client machines receive the kernel, a non-hostonly 
initramfs created with dracut, and a kernel command line containing
"root=iscsi..." to locate the root device (see attachments).
This setup worked fine for us since Fedora 20.
However, after upgrading to Fedora 23, the boot process fails when 
trying to mount the iscsi root to /sysroot.
Interestingly, the iscsi target is already connected properly at this point, 
i.e. the block device shows up (/dev/sdb). Furthermore, /dev/root correctly points on this block device, and when executing mount -a, /sysroot is
mounted as expected. The problem seems to be caused by the auto-generated file
/run/systemd/generator/sysroot.mount, which can not be handled correctly
by the mount command.
Despite the hostonly="no", we do not use any non-default dracut config.

We attach the following files and information below (please note that personal information has been anonymized):
1) cmdline - the kernel command line passed during PXE-boot
2) dracut-shell_fstab - the /etc/fstab found in the dracut emergency shell
3) dracut-shell_sysroot.mount - the above mentioned sysroot.mount file which causes the error
4) dracut-shell_systemctl-status-sysroot.mount - the output of systemctl status sysroot.mount
executed in the dracut emergency shell
5) fstab - the fstab file of the root file system
6) rdsosreport.txt - auto-generated by dracut

If we can help by providing further information please don't hesitate to ask.



Version-Release number of selected component (if applicable):
Fedora 23
dracut  Version: 043 Release: 61.git20151120.fc23
systemd Version: 222 Release: 8.fc23


How reproducible:
Set up PXE-boot with root=iscsi and perform PXE-boot.


Steps to Reproduce:
1.
2.
3.

Actual results:
Mounting /sysroot fails and dracut drops to an emergency shell.


Expected results:
/sysroot is mounted properly and the boot process continues.


Additional info:

1) cmdline
initrd=initrd.img_fedoraA ro root=iscsi:192.168.178.1::::iqn.2003-01.org.linux-iscsi.my-pc1.x8664:sn.disklessA readonlyroot vconsole.keymap=de BOOT_IMAGE=vmlinuz_fedoraA BOOTIF=01-aa-bb-cc-dd-ee-ff 

2) dracut-shell_fstab
/dev/root /sysroot auto ro,x-initrd.mount 0 0

3) dracut-shell_sysroot.mount
# Automatically generated by systemd-fstab-generator

[Unit]
SourcePath=/proc/cmdline
Documentation=man:fstab(5) man:systemd-fstab-generator(8)
Before=initrd-root-fs.target

[Mount]
What=iscsi:192.168.178.1::::iqn.2003-01.org.linux-iscsi.my-pc1.x8664:sn.disklessA
Where=/sysroot
Options=ro

4) dracut-shell_systemctl-status-sysroot.mount
● sysroot.mount - /sysroot
   Loaded: loaded (/proc/cmdline)
   Active: failed (Result: exit-code) since Mon 2015-11-30 17:45:24 UTC; 2min 52s ago
    Where: /sysroot
     What: iscsi:192.168.178.1::::iqn.2003-01.org.linux-iscsi.my-pc1.x8664:sn.disklessA
     Docs: man:fstab(5)
           man:systemd-fstab-generator(8)
  Process: 802 ExecMount=/usr/bin/mount iscsi:192.168.178.1::::iqn.2003-01.org.linux-iscsi.my-pc1.x8664:sn.disklessA /sysroot -o ro (code=exited, status=32)

Nov 30 17:45:24 my-pc2.my.domain.de systemd[1]: Mounting /sysroot...
Nov 30 17:45:24 my-pc2.my.domain.de mount[802]: mount.nfs: Failed to resolve server iscsi: No address associated with hostname
Nov 30 17:45:24 my-pc2.my.domain.de systemd[1]: sysroot.mount: Mount process exited, code=exited status=32
Nov 30 17:45:24 my-pc2.my.domain.de systemd[1]: Failed to mount /sysroot.
Nov 30 17:45:24 my-pc2.my.domain.de systemd[1]: sysroot.mount: Unit entered failed state.

5) fstab
# rootfs
UUID=5b600a5a-a9ff-47ad-af07-32208aedbc4d /   ext4   defaults    1 1

# home
192.168.178.1:/home  /home  nfs4  sec=krb5,rw,noatime,nodiratime,noacl 0 0

6) rdsosreport.txt
See attached file