Relay

This scenario shows how to configure service dhcp-relay. The relay agent must be used when the DHCP server and the DHCP clients are not connected to the same layer 2 domain.

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Test DHCP Relay

Description

This example demonstrates how to configure a DHCP relay instance in DUT0 to forward DHCP requests from DUT2 to DUT1.

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 vif 100 address 10.0.0.2/24
set interfaces ethernet eth1 vif 200 address 20.0.0.2/24
set service dhcp-relay INS downstream-interface eth1.200
set service dhcp-relay INS server 10.0.0.1
set service dhcp-relay INS upstream-interface eth0.100
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 vif 100 address 10.0.0.1/24
set protocols static route 0.0.0.0/0 next-hop 10.0.0.2
set service dhcp-server shared-network dummy subnet 10.0.0.1/32
set service dhcp-server shared-network remote subnet 20.0.0.0/24 start 20.0.0.50 stop 20.0.0.50
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Set the following configuration in DUT2 :

set interfaces ethernet eth0 vif 200 address dhcp
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 4: Ping IP address 10.0.0.1 from DUT0:

admin@DUT0$ ping 10.0.0.1 count 1 size 56 timeout 1
Show output
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
64 bytes from 10.0.0.1: icmp_seq=1 ttl=64 time=0.328 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.328/0.328/0.328/0.000 ms

Step 5: Run command interfaces ethernet show at DUT2 and check if output contains the following tokens:

20.0.0.50
Show output
---------------------------------------------------------------------
  Name             IP Address           Admin  Oper  Vrf  Description
---------------------------------------------------------------------
    eth0  fe80::dcad:beff:feef:6c20/64  up     up
eth0.200  20.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
    eth1                                down   down
    eth2                                down   down
    eth3                                down   down

Test DHCP Relay With Giaddr

Description

This example demonstrates how to set the gateway IP address (giaddr) in the IP address. This value must be set in an IP address that the DHCP server can reach.

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 vif 100 address 10.0.0.2/24
set interfaces ethernet eth1 vif 200 address 20.0.0.2/24
set interfaces ethernet eth1 vif 200 address 20.0.0.3/24
set service dhcp-relay INS downstream-interface eth1.200
set service dhcp-relay INS server 10.0.0.1 giaddr 20.0.0.3
set service dhcp-relay INS upstream-interface eth0.100
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 vif 100 address 10.0.0.1/24
set protocols static route 0.0.0.0/0 next-hop 10.0.0.2
set service dhcp-server shared-network dummy subnet 10.0.0.1/32
set service dhcp-server shared-network remote subnet 20.0.0.0/24 start 20.0.0.50 stop 20.0.0.50
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Set the following configuration in DUT2 :

set interfaces ethernet eth0 vif 200 address dhcp
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 4: Ping IP address 10.0.0.1 from DUT0:

admin@DUT0$ ping 10.0.0.1 count 1 size 56 timeout 1
Show output
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
64 bytes from 10.0.0.1: icmp_seq=1 ttl=64 time=0.595 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.595/0.595/0.595/0.000 ms

Step 5: Run command interfaces ethernet show at DUT2 and check if output contains the following tokens:

20.0.0.50
Show output
---------------------------------------------------------------------
  Name             IP Address           Admin  Oper  Vrf  Description
---------------------------------------------------------------------
    eth0  fe80::dcad:beff:feef:6c20/64  up     up
eth0.200  20.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
    eth1                                down   down
    eth2                                down   down
    eth3                                down   down

Step 6: Run command system journal show | cat at DUT1 and check if output matches the following regular expressions:

DHCPACK on 20.0.0.50 to [^\)]+\) via 20.0.0.3
Show output
Mar 05 22:23:01.292237 osdx systemd-journald[1982]: Runtime Journal (/run/log/journal/870944ec2cb343ee825d9d66ec6747cc) is 960.0K, max 6.4M, 5.5M free.
Mar 05 22:23:01.296072 osdx systemd-journald[1982]: Received client request to rotate journal, rotating.
Mar 05 22:23:01.296161 osdx systemd-journald[1982]: Vacuuming done, freed 0B of archived journals from /run/log/journal/870944ec2cb343ee825d9d66ec6747cc.
Mar 05 22:23:01.304725 osdx OSDxCLI[632527]: User 'admin' executed a new command: 'system journal clear'.
Mar 05 22:23:01.529874 osdx OSDxCLI[632527]: User 'admin' executed a new command: 'system coredump delete all'.
Mar 05 22:23:02.912157 osdx OSDxCLI[632527]: User 'admin' entered the configuration menu.
Mar 05 22:23:02.993978 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Mar 05 22:23:03.068593 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Mar 05 22:23:03.172987 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network remote subnet 20.0.0.0/24 start 20.0.0.50 stop 20.0.0.50'.
Mar 05 22:23:03.243680 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Mar 05 22:23:03.347835 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'show working'.
Mar 05 22:23:03.404118 osdx ubnt-cfgd[717480]: inactive
Mar 05 22:23:03.430456 osdx INFO[717490]: FRR daemons did not change
Mar 05 22:23:03.459968 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Mar 05 22:23:03.480336 osdx (udev-worker)[717540]: Network interface NamePolicy= disabled on kernel command line.
Mar 05 22:23:03.622434 osdx dhcpd[717617]: Wrote 0 leases to leases file.
Mar 05 22:23:03.620376 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Mar 05 22:23:03.624650 osdx cfgd[1620]: [632527]Completed change to active configuration
Mar 05 22:23:03.630040 osdx dhcpd[717617]:
Mar 05 22:23:03.630159 osdx dhcpd[717617]: No subnet declaration for eth0 (no IPv4 addresses).
Mar 05 22:23:03.630196 osdx dhcpd[717617]: ** Ignoring requests on eth0.  If this is not what
Mar 05 22:23:03.630236 osdx dhcpd[717617]:    you want, please write a subnet declaration
Mar 05 22:23:03.630267 osdx dhcpd[717617]:    in your dhcpd.conf file for the network segment
Mar 05 22:23:03.630299 osdx dhcpd[717617]:    to which interface eth0 is attached. **
Mar 05 22:23:03.630329 osdx dhcpd[717617]:
Mar 05 22:23:03.637032 osdx OSDxCLI[632527]: User 'admin' committed the configuration.
Mar 05 22:23:03.644100 osdx dhcpd[717617]: Server starting service.
Mar 05 22:23:03.657497 osdx OSDxCLI[632527]: User 'admin' left the configuration menu.
Mar 05 22:23:04.341705 osdx dhcpd[717617]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Mar 05 22:23:05.342146 osdx dhcpd[717617]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Mar 05 22:23:05.342810 osdx dhcpd[717617]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Mar 05 22:23:05.379565 osdx dhcpd[717617]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3

Test DHCP Relay With GRE Tunnel

Description

This example demonstrates how to configure a DHCP relay that forwards DHCP requests to the DHCP server through a GRE tunnel (upstream).

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 vif 100 address 10.0.0.2/24
set interfaces ethernet eth1 vif 200 address 20.0.0.2/24
set interfaces tunnel tun1 address 1.0.0.2/32
set interfaces tunnel tun1 encapsulation gre
set interfaces tunnel tun1 local-address 10.0.0.2
set interfaces tunnel tun1 local-interface eth0.100
set interfaces tunnel tun1 nhrp holdtime 5
set interfaces tunnel tun1 nhrp nhs 1.0.0.1 nbma 10.0.0.1
set service dhcp-relay INS downstream-interface eth1.200
set service dhcp-relay INS server 1.0.0.1
set service dhcp-relay INS upstream-interface eth0.100
set service dhcp-relay INS upstream-interface tun1
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 vif 100 address 10.0.0.1/24
set interfaces tunnel tun1 address 1.0.0.1/32
set interfaces tunnel tun1 encapsulation gre
set interfaces tunnel tun1 local-address 10.0.0.1
set interfaces tunnel tun1 local-interface eth0.100
set interfaces tunnel tun1 nhrp
set protocols static route 0.0.0.0/0 next-hop 10.0.0.2
set protocols static route 20.0.0.0/24 next-hop 1.0.0.2
set service dhcp-server shared-network dummy subnet 1.0.0.1/32
set service dhcp-server shared-network remote subnet 20.0.0.0/24 start 20.0.0.50 stop 20.0.0.50
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Set the following configuration in DUT2 :

set interfaces ethernet eth0 vif 200 address dhcp
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 4: Ping IP address 10.0.0.1 from DUT0:

admin@DUT0$ ping 10.0.0.1 count 1 size 56 timeout 1
Show output
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
64 bytes from 10.0.0.1: icmp_seq=1 ttl=64 time=0.350 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.350/0.350/0.350/0.000 ms

Step 5: Ping IP address 1.0.0.1 from DUT0:

admin@DUT0$ ping 1.0.0.1 count 1 size 56 timeout 1
Show output
PING 1.0.0.1 (1.0.0.1) 56(84) bytes of data.
64 bytes from 1.0.0.1: icmp_seq=1 ttl=64 time=0.373 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.373/0.373/0.373/0.000 ms

Step 6: Run command interfaces ethernet show at DUT2 and check if output contains the following tokens:

20.0.0.50
Show output
---------------------------------------------------------------------
  Name             IP Address           Admin  Oper  Vrf  Description
---------------------------------------------------------------------
    eth0  fe80::dcad:beff:feef:6c20/64  up     up
eth0.200  20.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
    eth1                                down   down
    eth2                                down   down
    eth3                                down   down

Test DHCP Relay With Multiple Instances

Description

This example demonstrates how to configure multiple DHCP relay instances.

Scenario

Step 1: Set the following configuration in DUT0 :

set interfaces ethernet eth0 vif 100 address 10.0.0.2/24
set interfaces ethernet eth1 vif 200 address 20.0.0.2/24
set interfaces ethernet eth1 vif 300 address 30.0.0.2/24
set service dhcp-relay INS downstream-interface eth1.200
set service dhcp-relay INS server 10.0.0.1
set service dhcp-relay INS upstream-interface eth0.100
set service dhcp-relay INS2 downstream-interface eth1.300
set service dhcp-relay INS2 server 10.0.0.1
set service dhcp-relay INS2 upstream-interface eth0.100
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces ethernet eth0 vif 100 address 10.0.0.1/24
set protocols static route 0.0.0.0/0 next-hop 10.0.0.2
set service dhcp-server shared-network dummy subnet 10.0.0.1/32
set service dhcp-server shared-network remote subnet 20.0.0.0/24 start 20.0.0.50 stop 20.0.0.50
set service dhcp-server shared-network remote2 subnet 30.0.0.0/24 start 30.0.0.50 stop 30.0.0.50
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Set the following configuration in DUT2 :

set interfaces ethernet eth0 vif 200 address dhcp
set interfaces ethernet eth0 vif 300 address dhcp
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 4: Ping IP address 10.0.0.1 from DUT0:

admin@DUT0$ ping 10.0.0.1 count 1 size 56 timeout 1
Show output
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
64 bytes from 10.0.0.1: icmp_seq=1 ttl=64 time=0.245 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.245/0.245/0.245/0.000 ms

Step 5: Run command interfaces ethernet show at DUT2 and check if output contains the following tokens:

20.0.0.50
Show output
---------------------------------------------------------------------
  Name             IP Address           Admin  Oper  Vrf  Description
---------------------------------------------------------------------
    eth0  fe80::dcad:beff:feef:6c20/64  up     up
eth0.200  20.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
eth0.300  30.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
    eth1                                down   down
    eth2                                down   down
    eth3                                down   down

Step 6: Run command interfaces ethernet show at DUT2 and check if output contains the following tokens:

30.0.0.50
Show output
---------------------------------------------------------------------
  Name             IP Address           Admin  Oper  Vrf  Description
---------------------------------------------------------------------
    eth0  fe80::dcad:beff:feef:6c20/64  up     up
eth0.200  20.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
eth0.300  30.0.0.50/24                  up     up
          fe80::dcad:beff:feef:6c20/64
    eth1                                down   down
    eth2                                down   down
    eth3                                down   down

Step 7: Run command system journal show | cat at DUT1 and check if output matches the following regular expressions:

DHCPACK on 20.0.0.50 to [^\)]+\) via 20.0.0.2
DHCPACK on 30.0.0.50 to [^\)]+\) via 30.0.0.2
Show output
Mar 05 22:23:31.256122 osdx systemd-journald[1982]: Runtime Journal (/run/log/journal/870944ec2cb343ee825d9d66ec6747cc) is 928.0K, max 6.4M, 5.5M free.
Mar 05 22:23:31.256619 osdx systemd-journald[1982]: Received client request to rotate journal, rotating.
Mar 05 22:23:31.256664 osdx systemd-journald[1982]: Vacuuming done, freed 0B of archived journals from /run/log/journal/870944ec2cb343ee825d9d66ec6747cc.
Mar 05 22:23:31.265853 osdx OSDxCLI[632527]: User 'admin' executed a new command: 'system journal clear'.
Mar 05 22:23:31.446700 osdx OSDxCLI[632527]: User 'admin' executed a new command: 'system coredump delete all'.
Mar 05 22:23:32.955606 osdx OSDxCLI[632527]: User 'admin' entered the configuration menu.
Mar 05 22:23:33.077378 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Mar 05 22:23:33.132062 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Mar 05 22:23:33.237711 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network remote subnet 20.0.0.0/24 start 20.0.0.50 stop 20.0.0.50'.
Mar 05 22:23:33.291806 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Mar 05 22:23:33.406108 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network remote2 subnet 30.0.0.0/24 start 30.0.0.50 stop 30.0.0.50'.
Mar 05 22:23:33.471344 osdx OSDxCLI[632527]: User 'admin' added a new cfg line: 'show working'.
Mar 05 22:23:33.558274 osdx ubnt-cfgd[718487]: inactive
Mar 05 22:23:33.586961 osdx INFO[718499]: FRR daemons did not change
Mar 05 22:23:33.620496 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Mar 05 22:23:33.642965 osdx (udev-worker)[718549]: Network interface NamePolicy= disabled on kernel command line.
Mar 05 22:23:33.764831 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Mar 05 22:23:33.767214 osdx dhcpd[718626]: Wrote 0 leases to leases file.
Mar 05 22:23:33.768677 osdx cfgd[1620]: [632527]Completed change to active configuration
Mar 05 22:23:33.781125 osdx OSDxCLI[632527]: User 'admin' committed the configuration.
Mar 05 22:23:33.798292 osdx OSDxCLI[632527]: User 'admin' left the configuration menu.
Mar 05 22:23:33.802503 osdx dhcpd[718626]:
Mar 05 22:23:33.802509 osdx dhcpd[718626]: No subnet declaration for eth0 (no IPv4 addresses).
Mar 05 22:23:33.802511 osdx dhcpd[718626]: ** Ignoring requests on eth0.  If this is not what
Mar 05 22:23:33.802514 osdx dhcpd[718626]:    you want, please write a subnet declaration
Mar 05 22:23:33.802516 osdx dhcpd[718626]:    in your dhcpd.conf file for the network segment
Mar 05 22:23:33.802518 osdx dhcpd[718626]:    to which interface eth0 is attached. **
Mar 05 22:23:33.802520 osdx dhcpd[718626]:
Mar 05 22:23:33.816590 osdx dhcpd[718626]: Server starting service.
Mar 05 22:23:34.470157 osdx dhcpd[718626]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Mar 05 22:23:34.618010 osdx dhcpd[718626]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Mar 05 22:23:35.470708 osdx dhcpd[718626]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 05 22:23:35.472232 osdx dhcpd[718626]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 05 22:23:35.490454 osdx dhcpd[718626]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 05 22:23:35.618288 osdx dhcpd[718626]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Mar 05 22:23:35.619764 osdx dhcpd[718626]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Mar 05 22:23:35.633496 osdx dhcpd[718626]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2