Static IP

By default, the device receives its IP address from the network's DHCP server. With a static IP configuration, it always uses the same address, which is useful when other devices or services need to reach it at a known address. You can set the configuration in your sketch, and users can set it in the captive portal while they connect the device to their network.

Configure from the captive portalCopy Anchor Link

When users enter the network password, they can turn on Static IP and enter the IP address, gateway, subnet mask and up to two DNS servers. The DNS servers are optional; when none is given, the gateway is used as the DNS server. The portal validates the format of each address, and the device validates the configuration as a whole before it connects (see Validation).

The configuration is saved together with the WiFi credentials once the device connects successfully. The next time the portal opens, the saved configuration is filled in.

In NetWizard Lite, the Static IP option is shown but locked, with a note that it is available in NetWizard Pro.

MethodsCopy Anchor Link

setStaticIP()Copy Anchor Link

bool setStaticIP(IPAddress ip, IPAddress gateway, IPAddress subnet,
                 IPAddress dns1 = IPAddress(0, 0, 0, 0),
                 IPAddress dns2 = IPAddress(0, 0, 0, 0));

Validates the configuration and saves it to persistent storage. Returns true if the configuration is valid, or false if it is rejected, in which case the current configuration is kept. The configuration applies to the next connection, so call it before autoConnect().

void setup() {
  // ...
  NW.setStaticIP(IPAddress(192, 168, 1, 50), IPAddress(192, 168, 1, 1), IPAddress(255, 255, 255, 0));
  NW.autoConnect("NetWizard Demo", "");
  // ...
}

setDHCP()Copy Anchor Link

void setDHCP();

Removes the static IP configuration from memory and persistent storage. From the next connection, the device obtains its address with DHCP.

NW.setDHCP();

isStaticIP()Copy Anchor Link

bool isStaticIP();

Returns true if a static IP configuration is active.

if (NW.isStaticIP()) {
  // ...
}

ValidationCopy Anchor Link

A configuration, whether set with setStaticIP() or submitted from the portal, is accepted only if:

• the IP address and the gateway are set,
• the subnet mask is contiguous, between 255.0.0.0 and 255.255.255.254,
• the gateway is in the same subnet as the IP address and differs from it, and
• the IP address is not the network or broadcast address of the subnet.

A submission from the portal that fails these checks is rejected, and the portal shows an error.

NotesCopy Anchor Link

• reset() and erase() also remove the saved static IP configuration.
• Read the address in use with localIP(), gatewayIP() and subnetMask().
• An address that is valid in form can still conflict with another device or lie outside the network's range. Choose an address outside the DHCP pool of the router.