DHCP Client Configuration

DHCP Client Configuration

Version Info

RouterOS 7.16 | Min: v6.0+ | ⏱️ 5 minutes | 🟢 Beginner

Tested on: 7.16 7.14 7.12

Version-specific notes

• v7.0: Added default-route-tables for VRF support and check-gateway=bgd option
• v6.43: Added special-classless option for add-default-route
• v6.x: Same commands work on RouterOS 6.x but some v7 features unavailable

TL;DR (Quick Start)

For the impatient: enable DHCP client on your WAN interface to get an IP from your ISP.

/ip dhcp-client add interface=ether1 disabled=no

Verify with:

/ip dhcp-client print

Look for status=bound and an assigned IP address.

Overview

What this does: DHCP (Dynamic Host Configuration Protocol) Client enables automatic IP address configuration on MikroTik RouterOS interfaces. The client receives an IP address, netmask, default gateway, and DNS/NTP server addresses from a DHCP server.

When to use this:

• WAN connections to ISPs that provide dynamic IP addresses
• Automated network configuration without manual IP setup
• Multi-WAN failover setups with dynamic addressing
• Any scenario where you need dynamic IP assignment from an upstream DHCP server

Prerequisites:

• An Ethernet-like interface (Ethernet, VLAN, Bridge, Wireless)
• No static IP address configured on the same interface
• Access to a network with a DHCP server (typically your ISP or upstream router)

Configuration Steps

Step 1: Add DHCP Client to WAN Interface

Enable DHCP client on your WAN interface. This will automatically request an IP address from the upstream DHCP server.

/ip dhcp-client add interface=ether1 disabled=no

By default, this configuration will:

• Accept and use DNS servers from the DHCP server (use-peer-dns=yes)
• Accept and use NTP servers from the DHCP server (use-peer-ntp=yes)
• Install a default route via the received gateway (add-default-route=yes)

Step 2: Verify Lease Acquisition

Check that the DHCP client successfully obtained an IP address.

/ip dhcp-client print detail

Expected output:

Flags: D - dynamic, X - disabled, I - invalid
 0   interface=ether1 add-default-route=yes default-route-distance=1
     use-peer-dns=yes use-peer-ntp=yes dhcp-options=hostname,clientid
     status=bound address=192.168.1.100/24 gateway=192.168.1.1
     dhcp-server=192.168.1.1 primary-dns=8.8.8.8 expires-after=23h45m

The key indicator is status=bound with a valid IP address.

Step 3: Confirm Default Route

Verify the default route was installed correctly.

/ip route print where dst-address=0.0.0.0/0

Expected output:

Flags: D - dynamic, A - active, c - connect, d - dhcp
 #   DST-ADDRESS    GATEWAY      DISTANCE
 0 DAd 0.0.0.0/0    192.168.1.1  1

The d flag indicates the route was added dynamically by DHCP.

Common Scenarios

Scenario: Use Your Own DNS Servers

If you want to use custom DNS servers instead of those provided by your ISP:

/ip dhcp-client add interface=ether1 disabled=no use-peer-dns=no use-peer-ntp=no

Then configure your preferred DNS servers:

/ip dns set servers=1.1.1.1,8.8.8.8

Scenario: Multi-WAN Failover

For setups with two ISP connections where the second is a backup:

# Primary WAN - lower distance = preferred
/ip dhcp-client add interface=ether1 disabled=no default-route-distance=1 \
    use-peer-dns=no use-peer-ntp=no

# Secondary WAN - higher distance = backup
/ip dhcp-client add interface=ether2 disabled=no default-route-distance=2 \
    use-peer-dns=no use-peer-ntp=no

For automatic failover when primary link fails:

/ip dhcp-client set [find interface=ether1] check-gateway=ping
/ip dhcp-client set [find interface=ether2] check-gateway=ping

Scenario: Custom Hostname for ISP

Some ISPs require or prefer a specific hostname:

/ip dhcp-client set [find interface=ether1] host-name="my-router"

Scenario: LTE Interface DHCP Client

LTE interfaces create dynamic DHCP clients that cannot be edited directly. Configure via APN profile instead:

/interface lte apn set [find name=default] default-route-distance=2 use-peer-dns=no add-default-route=yes

Scenario: DHCP Client with Script (Advanced)

For advanced multi-WAN setups requiring custom route management:

/ip dhcp-client add interface=ether1 disabled=no add-default-route=no script={
    :if ($bound=1) do={
        /ip route add gateway=$"gateway-address" comment="WAN1-DHCP"
        :log info ("DHCP bound: " . $"lease-address" . " via " . $"gateway-address")
    } else={
        /ip route remove [find comment="WAN1-DHCP"]
        :log info "DHCP lease lost"
    }
}

Script variables available:

Variable	Description
$bound	1 = lease acquired, 0 = lease lost
$"lease-address"	Assigned IP address
$"gateway-address"	Gateway from DHCP server
$interface	Interface name
$"server-address"	DHCP server IP

Verification

Confirm your DHCP client configuration is working:

Check 1: Verify Client is Bound

/ip dhcp-client print detail where status=bound

Expected: Status shows bound with valid address and gateway.

Check 2: Verify Default Route

/ip route print where dst-address=0.0.0.0/0 gateway-status~"reachable"

Expected: Active route with reachable gateway.

Check 3: Verify DNS (if use-peer-dns=yes)

/ip dns print

Expected: dynamic=yes with servers matching DHCP-provided values.

Check 4: Test Connectivity

/tool ping 8.8.8.8 count=3

Expected: 3 packets transmitted, 3 received.

Troubleshooting

Symptom	Cause	Solution
Status stuck on “searching”	No DHCP server responding	Verify physical connection; check if ISP requires specific options
Status stuck on “searching”	ISP hostname bug	Try changing hostname: /ip dhcp-client set 0 host-name="router"
Status stuck on “searching”	RouterOS 7.3.0+ option ordering	Add Option 57 (see Community Tips below)
Default route shows “invalid”	Conflicting static route exists	Remove static default route or adjust distances
Multiple default routes	Multiple DHCP clients with same distance	Set different default-route-distance values
DNS not updating	IPv6 also providing DNS	Set use-peer-dns=no on IPv6 DHCP client too
Bridge not getting IP	No physical port in bridge	Ensure at least one active port in bridge
Can’t edit LTE DHCP client	LTE creates dynamic client	Configure via /interface lte apn instead

Common Mistakes

• Don’t configure static IP on the same interface - DHCP client and static IP conflict
• Don’t forget route distances in multi-WAN - Without different distances, routes will conflict
• Don’t expect firewall to block rogue DHCP - IP firewall does NOT apply to DHCP client traffic; use bridge filtering if needed
• Remember Option 121 precedence - Classless static routes (Option 121) override the default gateway (Option 3) per RFC 3442

Community Tips

Virgin Media / Cadant Server Fix: RouterOS 7.3.0+ changed DHCP option ordering which breaks some ISP servers. Add Option 57 as a workaround:

/ip dhcp-client option add name=option57 code=57 value=0x0240
/ip dhcp-client set [find interface=ether1] dhcp-options=clientid,option57

CHR Auto-Injection Prevention: CHR may auto-create DHCP client on ether1. To prevent this, put ether1 in a bridge.

Script Debugging: If your DHCP script isn’t working, check syntax with:

:log warning ("Gateway: " . $"gateway-address")

Note: Parentheses around concatenation are required in log statements.

DHCP Client Status Reference

Status	Description
bound	Lease acquired successfully, client has valid IP
searching	Sending DHCPDISCOVER, waiting for server offers
requesting	Sent DHCPREQUEST, waiting for acknowledgment
rebinding	Lease expiring, trying to extend with any server
stopped	Client is disabled or stopped
error	Error occurred during DHCP process

Related Topics

Prerequisites

• IP Address Configuration - understand static IP assignment (DHCP client is the alternative)

Related DHCP Topics

• DHCP Server - configure your router as a DHCP server for downstream clients
• DHCP Relay - forward DHCP requests across network segments
• IP Pools - address pool management for DHCP servers

Next Steps

• Static Routes - manual routing configuration
• NAT Masquerade - enable internet sharing for LAN devices
• DNS Server - local DNS configuration

IPv6 Alternative

• DHCPv6 Client - IPv6 DHCP client with prefix delegation

Reference

• MikroTik DHCP Documentation
• Version changes:
  • v7.0: Added default-route-tables for VRF, check-gateway=bgd
  • v6.43: Added special-classless for add-default-route

DHCP Options Requested

RouterOS DHCP client automatically requests these options from the server:

Option	Name	Purpose
1	Subnet Mask	Network mask for assigned address
3	Gateway List	Default gateway addresses
6	DNS Server List	DNS resolver addresses
33	Static Routes	Classful static routes
42	NTP Server List	Time server addresses
43	Vendor Specific	Vendor-specific information
121	Classless Static Routes	CIDR routes (takes precedence over Option 3 per RFC 3442)
138	CAPWAP AC Addresses	Controller addresses for CAPsMAN

Key Properties Reference

Property	Type	Default	Description
interface	string	-	Interface for DHCP client (required)
disabled	yes/no	yes	Whether client is disabled
add-default-route	yes/no/special-classless	yes	Install default route from DHCP
use-peer-dns	yes/no	yes	Accept DNS servers from DHCP
use-peer-ntp	yes/no	yes	Accept NTP servers from DHCP
default-route-distance	0-255	1	Administrative distance for default route
host-name	string	system identity	Hostname sent to DHCP server
client-id	string	MAC address	Custom client identifier
check-gateway	none/arp/ping/bgd	none	Gateway reachability check method
script	script	-	Script executed on lease events