MYLan Beginner's Guide

STEP ZERO

Before you start

Check you have these. The first four are essential.

NeededA Windows laptop or a MacWindows 10 or 11, or macOS 12 or later. Nothing else to install: MYLan brings everything it needs.
NeededA wired network portThe square socket on the laptop (RJ45). Most Macs and thin laptops need a USB-C network adapter. Wi-Fi won't do.
NeededA network switchAny switch, managed or not. The laptop and every show device plug into it.
NeededAdministrator passwordMYLan changes the laptop's network settings, so Windows asks to allow it and a Mac asks for your password.
RecommendedA network of your ownA switch that only your show kit is plugged into. MYLan must never be connected to the venue's or office network.
OptionalWi-Fi on the laptopFine to leave on for internet, as long as the venue Wi-Fi doesn't use addresses starting 192.168.1. (MYLan checks this for you).

One rule above all. Only run MYLan on a network where nothing else hands out addresses. If you plug it into a venue, hotel or office network, it competes with their router and can knock their devices offline. Use your own switch.

ONE-TIME SETUP

Getting MYLan

MYLan is a standalone app. Pick the download for your laptop.

WinWindows

Run the installerOpen MYLan-Setup-2.2.0-win-x64.exe. Leave Add Windows Firewall rule for MYLan ticked.
If Windows warns you"Windows protected your PC" appears for apps from outside the Store. Click More info, then Run anyway.
Open MYLan from the Start menuClick Yes when Windows asks to let it make changes. It needs this every time.

No installer rights? Use MYLan-portable-win-x64.exe: copy it anywhere and double-click it.

MacMac

Open the DMGUse MYLan-2.2.0-osx-arm64.dmg for Apple Silicon (M1 and later) or osx-x64 for Intel.
Double-click Install MYLan.commandType your Mac password when asked. If macOS won't open it, go to System Settings → Privacy & Security and click Open Anyway.
Start it with Run MYLan.commandIt's in your Applications folder. A Terminal window asks for your password, then MYLan opens. Leave the Terminal window open while MYLan runs.

Not sure which Mac you have? Apple menu → About This Mac. "Chip: Apple M…" means Apple Silicon.

Using the older MYLan 1.2 for Windows? Everything below still applies. It has no settings fields: it always uses 192.168.1.1 and hands out 192.168.1.50 to 192.168.1.150.

JARGON, DECODED

Words you'll see

These are the only terms the guide and the app use.

DHCP: The system that hands out addresses automatically. MYLan is a DHCP server; your devices are DHCP clients.
IP address: A device's address on the network, like 192.168.1.51. Two devices must never share one.
Subnet: The group of addresses that can talk to each other directly. 255.255.255.0 means "everything starting 192.168.1.": up to 254 devices.
Pool: The range MYLan hands out from. The default, .50 to .150, is 101 addresses.
Lease: An address on loan to one device for 8 hours. Devices renew it on their own, so in practice they keep the same address.
MAC address: A device's fixed hardware ID, like 00-1D-C1-0A-22-F3. MYLan uses it to recognise each device.
Adapter: The laptop's network port: the built-in Ethernet socket or a USB network adapter.
Static address: An address typed into a device by hand instead of coming from DHCP. Used for consoles and other kit that must never move.
Gateway: The way out to the internet. Show networks usually have none, so MYLan leaves it blank.
DNS: The service that turns names into addresses. Only needed for internet access; blank by default.

ABOUT FIVE MINUTES

Your first show network

Do these in order.

Build the network.Cable the laptop's network port to your switch, and plug the show devices into the same switch. Switch everything on. Wait about 10 seconds for the link lights.
Open MYLan.The status at the top right reads Idle.
Choose the adapter.Next to Adapter, pick the wired port the switch is on. Only connected, wired ports are listed. If yours is missing, check the cable, then click ↻ Refresh NICs.
Leave the other settings as they are.The defaults suit almost every show. The settings explains when to change them.
Click ▶ Start.The status turns green and reads DHCP Running. The log shows DHCP server started on UDP port 67.
Watch devices arrive.Each one appears under Active Leases with its MAC address and IP. Devices that were already on may take up to a minute; unplugging and replugging one makes it ask straight away.
At the end of the show, click ■ Stop.MYLan puts the laptop's network port back how it was. Closing the window does the same.

Activity Log · example

[19:02:11] Using adapter: Ethernet 2
[19:02:11] Setting static IP 192.168.1.1/255.255.255.0...
[19:02:13] Static IP configured successfully.
[19:02:13] DHCP server started on UDP port 67.
[19:02:20] DISCOVER from 00-1D-C1-0A-22-F3
[19:02:20] Sent OFFER → 192.168.1.50
[19:02:20] REQUEST from 00-1D-C1-0A-22-F3
[19:02:20] Sent ACK → 192.168.1.50

Example log. Adapter names and MAC addresses will differ on your kit.

Write the addresses down. Devices normally keep the same address for the whole show, and MYLan remembers them if you restart it. If a console must always have the same address, give it a static address outside the pool instead: anything from 192.168.1.2 to 192.168.1.49, or .151 to .254.

WHAT EACH FIELD DOES

The settings

The settings are locked while MYLan is running. Click ■ Stop to change them.

Field	Default	Change it when
Adapter	First wired port	You have more than one wired port, for example a dock and a USB adapter.
Server IP	`192.168.1.1`	The laptop's own address. Change it if something else on your network already uses `.1`, or the venue Wi-Fi uses `192.168.1.` addresses. `10.10.10.1` is a good alternative.
Subnet	`255.255.255.0`	Almost never. Leave it unless a manufacturer tells you otherwise.
Pool	`.50` – `.150`	You have more than 101 devices, or you need a different range kept free for static addresses. Both ends must sit in the same subnet as the Server IP.
DNS	blank	Only if the show network has its own internet connection. Enter the router's address.
Gateway	blank	Only if a router on this network gives internet access. Enter that router's address, never the laptop's own.

Why are Gateway and DNS blank? The laptop doesn't pass traffic on to the internet. If MYLan told devices to use it as their way out, a show laptop that is also on Wi-Fi would try to reach the internet through the show network and find nothing there.

WHAT IT'S TELLING YOU

Reading the log

Every device joins in four messages: it asks, MYLan offers, it requests, MYLan confirms. Here's what the lines mean.

Line	Means
DISCOVER from …	A device has asked for an address.
Sent OFFER → …	MYLan offered it one.
REQUEST from …	The device said "yes please".
Sent ACK → …	Done. The device has its address and appears in Active Leases.
RELEASE from …	A device handed its address back, usually because it was shut down.
[NAK] … outside pool	A device asked to keep an address from another network. MYLan said no, and the device asks for a new one. Normal when you move kit between venues.
Ignoring REQUEST for DHCP server …	Another DHCP server is on this network. See When something goes wrong.
DECLINE from …	A device found someone already using its address. MYLan parks that address for 30 minutes and hands out another. Look for a device with that address typed in by hand.
[WARN] IP pool exhausted	Every address in the pool is in use. Make the pool bigger.

TROUBLESHOOTING

When something goes wrong

You see	Try this
Adapter list is empty	Plug the cable into a switch that's switched on, or connect your USB network adapter, then click ↻ Refresh NICs. Wi-Fi is deliberately left out.
… is already on the 192.168.1.1/… network	Another connection, usually the venue Wi-Fi, uses the same addresses. Disconnect it, or change Server IP and Pool to another range such as `10.10.10.1` with pool `10.10.10.50` – `10.10.10.150`.
Failed to set static IP	WinOpen MYLan again and click Yes when Windows asks. MacStart it with `Run MYLan.command`, not by opening the app directly.
… did not come up on the adapter	The cable is unplugged, the switch is off, or another device on the switch already uses the Server IP. Check the link lights and try again.
UDP port 67 is already in use	Something else on the laptop is already a DHCP server: another copy of MYLan, Windows Internet Connection Sharing, or macOS Internet Sharing. Close or turn it off, then Start again.
Ignoring REQUEST for DHCP server …	There's a second DHCP server on your switch, often a router or a venue connection plugged in by mistake. Find it and unplug it; two servers make devices pick addresses at random.
Running, but a device never appears	Check the device is set to DHCP (sometimes called "automatic" or "dynamic"), not a static address. Then unplug and replug its cable. WinIf nothing appears at all, Windows Firewall is blocking MYLan: reinstall with the firewall option ticked, or with the portable exe, click Allow when Windows Firewall asks.
Device shows 169.254.x.x	It gave up waiting for an address. Unplug and replug it now that MYLan is running.
Could not restore previous adapter IP configuration	WinSettings → Network & internet → Ethernet → IP assignment → Edit → Automatic (DHCP). MacSystem Settings → Network → your adapter → Details → TCP/IP → Using DHCP.

GOOD QUESTIONS

Questions

Can MYLan break the venue's network?

Only if you connect it to that network. MYLan answers only on the port you choose, and refuses to start if another connection uses the same addresses. Keep its switch separate and it can't reach anything else.

Will the laptop still have internet on Wi-Fi?

Yes. MYLan only changes the wired port you pick, and it doesn't make the show network the laptop's way to the internet.

Do devices keep the same address after a restart?

Usually yes. Leases last 8 hours, devices renew them automatically, and MYLan saves them, so after a restart a device normally gets its old address back. For kit that must never change, use a static address outside the pool.

How many devices can I connect?

101 with the default pool. Widen the pool, for example .20 to .250, for up to 231.

Why can't I use Wi-Fi?

The Wi-Fi port connects the laptop to someone else's network. Handing out addresses there would clash with their router.

Why does it need an administrator password?

It changes the laptop's network settings and uses a protected network port (67) that only administrators may open.

Does the Mac version work the same as Windows?

Yes: same window, same settings, same log. The only difference is how you start it, through Run MYLan.command.