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Version: 3.1.15 (stable)

Installing luadch

This document covers post-build deployment — what to do once BUILDING.md has produced a build/install/luadch/ directory. For configuring the hub afterwards, see CONFIGURATION.md.

What you have after a build​

cmake --install build produces a self-contained directory:

build/install/luadch/
├── luadch          (Linux) or Luadch.exe (Windows) — the hub binary
├── liblua.so       (Linux) or lua.dll (Windows)
├── libssl-3-x64.dll, libcrypto-3-x64.dll        (Windows only)
├── lib/                                          shared plugins (.so/.dll + .lua)
├── core/           Lua core modules
├── scripts/        bundled command / bot / utility scripts
├── cfg/            cfg.tbl + user.tbl (default templates)
├── certs/          TLS cert generation helpers
├── lang/           hub-side language files
├── docs/           embedded docs
└── log/            empty; the hub writes here at runtime

The directory is portable — copy it anywhere on a target machine and run from there. There are no absolute path assumptions in the build.

Linux deployment​

Where to put the install directory​

Conventional choices:

PathWhen to pick it
/opt/luadch/Single hub on a dedicated server
/srv/luadch/Same as above, FHS-recommended for served data
~/luadch/Per-user hub (no root needed)
/var/luadch/<name>/Multiple hubs sharing a host
# As root, deploy to /opt
sudo cp -r build/install/luadch /opt/
sudo chown -R luadch:luadch /opt/luadch    # see "service user" below

Service user​

Run the hub as an unprivileged user, never as root. Create one:

sudo useradd --system --home-dir /opt/luadch --shell /usr/sbin/nologin luadch

File permissions​

The two configuration tables hold credentials and registration state. Tighten their permissions so other local users on the host cannot read them:

sudo chmod 600 /opt/luadch/cfg/user.tbl
sudo chmod 600 /opt/luadch/cfg/cfg.tbl     # contains the dummy default password

The log/ directory must be writable by the service user:

sudo chmod 750 /opt/luadch/log

Everything else (core/, scripts/, lib/, …) can stay read-only for the service user — the hub does not modify its own code at runtime.

systemd unit​

Drop this into /etc/systemd/system/luadch.service:

[Unit]
Description=Luadch ADC Hub
After=network-online.target
Wants=network-online.target

[Service]
Type=simple
User=luadch
Group=luadch
WorkingDirectory=/opt/luadch
ExecStart=/opt/luadch/luadch
Restart=on-failure
RestartSec=5

# Hardening (optional but recommended)
NoNewPrivileges=true
ProtectSystem=strict
ReadWritePaths=/opt/luadch/log /opt/luadch/cfg /opt/luadch/scripts/data
ProtectHome=true
PrivateTmp=true

[Install]
WantedBy=multi-user.target

WorkingDirectory= is optional - the hub anchors its own runtime paths to the binary's directory at startup (Phase 6b / issue #12), so it works regardless of the CWD systemd hands it. We still set it explicitly above for clarity and so the unit reads the same on older releases that did require it.

Enable and start:

sudo systemctl daemon-reload
sudo systemctl enable --now luadch
sudo systemctl status luadch

Logs​

The hub writes to log/ inside the install directory. systemd captures stdout / stderr separately via journald:

sudo journalctl -u luadch -f          # live
sudo journalctl -u luadch --since today

Network / firewall​

  • TCP 5000 — plain ADC (adc://)
  • TCP 5001 — TLS ADC (adcs://)

Open whichever you actually use. For a public hub, you almost certainly only want TLS:

# UFW
sudo ufw allow 5001/tcp

# firewalld
sudo firewall-cmd --add-port=5001/tcp --permanent
sudo firewall-cmd --reload

If your hub is behind NAT, port-forward the same port to the host.

Windows deployment​

Where to put the install directory​

C:\luadch\ or D:\luadch\ works. The hub's only requirement is that its working directory at launch time is the install root.

Run as a service​

Windows does not natively run console executables as services. Use NSSM (the Non-Sucking Service Manager):

:: install
nssm install luadch C:\luadch\Luadch.exe
nssm set luadch AppDirectory C:\luadch
nssm set luadch DisplayName "Luadch ADC Hub"
nssm set luadch Description "DC++ ADC hub server"
nssm set luadch Start SERVICE_AUTO_START
nssm set luadch AppStdout C:\luadch\log\stdout.log
nssm set luadch AppStderr C:\luadch\log\stderr.log

:: start it
nssm start luadch

Manage afterwards via services.msc or nssm restart luadch etc.

Windows Defender / firewall​

Allow the binary on the firewall the first time you run it (netsh advfirewall firewall add rule name="Luadch ADCS" dir=in action=allow protocol=TCP localport=5001). If Defender quarantines Luadch.exe on a corporate-managed machine, add a path exclusion for C:\luadch\.

Backups​

What is worth backing up:

PathWhy
cfg/cfg.tblhub configuration, edited by you
cfg/user.tblregistered users + hashed credentials
cfg/user.tbl.bakrolling backup the hub maintains itself
scripts/data/*.tblper-script state (bans, chatlog, etc.)
certs/cacert.pem, serverkey.pem, servercert.pemTLS keys; users will see a different keyprint after a regen

Everything else (core/, scripts/*.lua, lib/, lang/) reproduces from a fresh build.

Rsync-style nightly backup script template:

#!/bin/sh
set -eu
DST=/var/backups/luadch
mkdir -p "$DST"
rsync -a --delete /opt/luadch/cfg/        "$DST"/cfg/
rsync -a --delete /opt/luadch/certs/      "$DST"/certs/
rsync -a --delete /opt/luadch/scripts/data/ "$DST"/scripts-data/

Updating the hub​

When you pull new code and rebuild:

# 1. New build
git pull
cmake --build build -j$(nproc)
cmake --install build              # writes to build/install/luadch/

# 2. Stop the running hub
sudo systemctl stop luadch

# 3. Replace the read-only parts only — keep cfg/, certs/, scripts/data/, log/
sudo rsync -a --delete \
    --exclude='/cfg/' --exclude='/certs/' --exclude='/log/' \
    --exclude='/scripts/data/' \
    build/install/luadch/ /opt/luadch/

# 4. Restart
sudo systemctl start luadch

The exclude list is the contract: those are the directories the running hub considers state, and the new build's defaults must not clobber them.

If a release notes mentions a cfg/cfg.tbl migration, copy any new keys from build/install/luadch/cfg/cfg.tbl into /opt/luadch/cfg/cfg.tbl manually before restarting.

Verifying the install​

Once running:

# port bound?
ss -tln | grep -E ':500[01]'

# hub responding to ADC handshake?
printf 'HSUP ADBASE ADTIGR\n' | nc -q1 127.0.0.1 5000 | head
# Expect: ISUP ... / ISID ... / IINF ...

# active sessions (after first connect)
grep -c "init.lua" /opt/luadch/log/*.log    # rough heartbeat

Then point an ADC client (e.g. AirDC++) at adcs://your.host:5001 (TLS) or adc://your.host:5000 (plain) and log in as dummy / test for the first time. Read CONFIGURATION.md for the register-yourself / delete-dummy steps before opening the hub to real users.