Network error encountered while following the quasar.config

Error message

Network error encountered while following the quasar.config file host/port config. Reconfigure and save the file again.

What it means

During config computation, onAddress verifies the configured devServer host/port; if it fails (bad host or no available port), it returns null and #computeConfig reports this network-error message. Fatal when shouldFail; otherwise it warns and aborts this config pass, prompting you to fix host/port and re-save (watch mode reloads the file).

Source

Thrown at app-vite/lib/quasar-config-file.js:1027

        cfg.devServer.host = this.#address.to.host
        cfg.devServer.port = this.#address.to.port
      } else {
        const addr = {
          host: cfg.devServer.host,
          port: cfg.devServer.port
        }
        const to = this.#opts.verifyAddress
          ? await onAddress(addr, this.#ctx.modeName)
          : addr

        // if network error while running
        if (to === null) {
          const msg =
            'Network error encountered while following the quasar.config file host/port config.'

          if (this.#shouldFail) fatal(msg, 'FAIL')

          warn(msg + ' Reconfigure and save the file again.\n')
          return
        }

        cfg.devServer = merge({ open: true }, cfg.devServer, to)
        this.#address = {
          from: addr,
          to: {
            host: cfg.devServer.host,
            port: cfg.devServer.port
          }
        }
      }
    }
    // else for production:
    else if (!Array.isArray(cfg.ssr.prodScriptNamedExport)) {
      cfg.ssr.prodScriptNamedExport = cfg.ssr.prodScriptNamedExport
        ? [cfg.ssr.prodScriptNamedExport]
        : []

View on GitHub (pinned to 4841521b5f)

Solutions

Fix devServer.host in quasar.config — use 0.0.0.0, localhost, or a valid interface IP — and save to trigger re-computation.
Choose a lower/free devServer.port so findClosestOpenPort can find one.
Check network interfaces (ip addr / ifconfig) to confirm the host IP exists.
Restart `quasar dev` after fixing if file-watch didn't retrigger.

Example fix

// before (quasar.config)
devServer: { host: '192.168.1.999', port: 65530 }
// after
devServer: { host: '0.0.0.0', port: 9000 }

Defensive patterns

Strategy: validation

Validate before calling

// Verify host exists on an interface before config save:
import { networkInterfaces } from 'node:os'
const host = cfg.devServer.host
const all = Object.values(networkInterfaces()).flat()
if (host !== '0.0.0.0' && host !== 'localhost' && !all.some(n => n?.address === host)) {
  console.warn(`Host ${host} not present on this machine`)
}

Prevention

Use 0.0.0.0 or localhost unless you need a specific interface.
Avoid pinning DHCP-assigned IPs in quasar.config; they change.
Choose a starting port well below 65535 so a free port can be found.
Re-check host/port after connecting to VPNs or switching networks.

When it happens

Trigger: quasar.config > devServer > host names an address not present on any network interface (ERROR_NETWORK_ADDRESS_NOT_AVAIL), or no free port can be found from the configured starting port (ERROR_NETWORK_PORT_NOT_AVAIL), while opts.verifyAddress is active (dev run or config watch).

Common situations: Setting host to an external/VPN IP that is currently down or moved; typo in host (e.g. 'localhst'); all ports from the configured one upward are blocked; firewall/network change while the dev server watches the config file.

Related errors

AI-assisted analysis of quasarframework/quasar@4841521b5f (2026-08-30). Data as JSON: /api/errors/fee027ebd6d90407. Report an issue: GitHub.