Bug#838028: systemd-shutdown hangs indefinitely when rebooting or shutting down with iscsi share connected

[Colby Ross]

Package: systemd
Version: 231-4

Kernel version 4.6.0-1-amd64

I am currently running debian stretch/sid alpha 7, all up to date, no 
testing repos or anything added. I have open-iscsi installed via apt 
install open-iscsi. I have connected to an iSCSI share on my local 
network, which is working fine. I can access the share, linux registers 
the share as a device at the kernel, and I can access it as normal. When 
rebooting, or shutting down, it appears systemd is not properly shutting 
down the iscsi connection, or something to that effect which causes the 
reboot or shutdown to halt at the end and go no further.

The following message appears at the end of the shutdown/reboot when it 
has hung:
sd 3:0:0:0: [sdb] Synchronizing SCSI cache
connection1:0: ping timeout of 5 secs expired, recv timeout 5, last rx 
4294943601, last ping 4294944852, now 4294946104
connection1:0: detected conn error (1022)

It appears that the open-iscsi service is not properly terminated, or 
may be terminated after the network interface has been brought down my 
systemd.   This problem does not occur on Debian Jessie 8.5. It is worth 
noting that I have the virt-manager package installed and have added the 
iscsi share via virt-manager for this machine. It is a virtualized 
machine, however it also does this on a physical box running an 
identical setup. I searched for similar bugs and found one relevant to 
NFS shares, but have been unable to locate one regarding iSCSI and systemd.

I have a baseline knowledge of linux and working around it, but I have 
been unable to figure out how to fix this, or if its really a bug and 
not just a configuration error on my part, but given the same 
configuration under 8.5 (Jessie) works flawlessly across reboots and 
shutdowns, I'm thinking it may be a bug.