Comment 9 for bug 2060745

Verificaton done on noble-proposed.

Thanks for the detailed test steps!
(I updated the last command from 'nbd-client -d nbd0' to 'nbd-client nbd0',
which reflects the test step without the fix, in 'Now, trigger the problem').

Environment:
---

lxc launch ubuntu:noble --vm mfo-noble-vm
lxc shell mfo-noble-vm
apt update -y && apt install -y nbd-client nbd-server

modprobe nbd
truncate -s 1T /vol-0.img

cat <<EOF >/etc/nbd-server/conf.d/exports.conf
[vol0]
exportname = /vol-0.img
EOF

systemctl restart nbd-server.service

$ nbd-client localhost /dev/nbd0 -name vol0
Negotiation: ..size = 1048576MB
Connected /dev/nbd0

nbd-client -d /dev/nbd0

cat <<EOF >>/etc/nbdtab
nbd0 localhost vol0
EOF

Before:
---

# dpkg -s nbd-client | grep Version:
Version: 1:3.26.1-1build1

# nbd-client nbd0
Error: Socket failed: Connection refused

After:
---

sed '/^Suites: .*noble-updates/ s/$/ noble-proposed/' -i /etc/apt/sources.list.d/ubuntu.sources
apt update && apt install -y -t noble-proposed nbd-client nbd-server

# apt policy nbd-client
nbd-client:
  Installed: 1:3.26.1-1ubuntu0.1
  Candidate: 1:3.26.1-1ubuntu0.1
  Version table:
 *** 1:3.26.1-1ubuntu0.1 100
        100 http://archive.ubuntu.com/ubuntu noble-proposed/universe amd64 Packages
        100 /var/lib/dpkg/status
     1:3.26.1-1build1 500
        500 http://archive.ubuntu.com/ubuntu noble/universe amd64 Packages

# dpkg -s nbd-client | grep Version:
Version: 1:3.26.1-1ubuntu0.1

# nbd-client nbd0
Connected /dev/nbd0