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=0.288 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.288/0.288/0.288/0.000 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=0.370 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.370/0.370/0.370/0.000 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
Feb 19 09:38:24.307108 osdx systemd-journald[1946]: Runtime Journal (/run/log/journal/23713d8b40eb43dfbc54dc8903f4bf64) is 964.0K, max 6.5M, 5.5M free.
Feb 19 09:38:24.307657 osdx systemd-journald[1946]: Received client request to rotate journal, rotating.
Feb 19 09:38:24.307703 osdx systemd-journald[1946]: Vacuuming done, freed 0B of archived journals from /run/log/journal/23713d8b40eb43dfbc54dc8903f4bf64.
Feb 19 09:38:24.319770 osdx OSDxCLI[2298]: User 'admin' executed a new command: 'system journal clear'.
Feb 19 09:38:24.514249 osdx OSDxCLI[2298]: User 'admin' executed a new command: 'system coredump delete all'.
Feb 19 09:38:25.984859 osdx OSDxCLI[2298]: User 'admin' entered the configuration menu.
Feb 19 09:38:26.131992 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Feb 19 09:38:26.211005 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Feb 19 09:38:26.294294 osdx OSDxCLI[2298]: 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'.
Feb 19 09:38:26.396892 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Feb 19 09:38:26.463959 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'show working'.
Feb 19 09:38:26.564198 osdx ubnt-cfgd[172836]: inactive
Feb 19 09:38:26.591309 osdx INFO[172846]: FRR daemons did not change
Feb 19 09:38:26.619260 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Feb 19 09:38:26.639649 osdx (udev-worker)[172894]: Network interface NamePolicy= disabled on kernel command line.
Feb 19 09:38:26.783839 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Feb 19 09:38:26.786161 osdx cfgd[1621]: [2298]Completed change to active configuration
Feb 19 09:38:26.787642 osdx dhcpd[172973]: Wrote 0 leases to leases file.
Feb 19 09:38:26.801041 osdx OSDxCLI[2298]: User 'admin' committed the configuration.
Feb 19 09:38:26.815694 osdx dhcpd[172973]:
Feb 19 09:38:26.815702 osdx dhcpd[172973]: No subnet declaration for eth0 (no IPv4 addresses).
Feb 19 09:38:26.815705 osdx dhcpd[172973]: ** Ignoring requests on eth0.  If this is not what
Feb 19 09:38:26.815709 osdx dhcpd[172973]:    you want, please write a subnet declaration
Feb 19 09:38:26.815711 osdx dhcpd[172973]:    in your dhcpd.conf file for the network segment
Feb 19 09:38:26.815715 osdx dhcpd[172973]:    to which interface eth0 is attached. **
Feb 19 09:38:26.815717 osdx dhcpd[172973]:
Feb 19 09:38:26.818573 osdx OSDxCLI[2298]: User 'admin' left the configuration menu.
Feb 19 09:38:26.823405 osdx dhcpd[172973]: Server starting service.
Feb 19 09:38:27.508936 osdx dhcpd[172973]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Feb 19 09:38:28.509625 osdx dhcpd[172973]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Feb 19 09:38:28.510468 osdx dhcpd[172973]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Feb 19 09:38:28.526670 osdx dhcpd[172973]: 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=0.501 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.501/0.501/0.501/0.000 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=0.301 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.301/0.301/0.301/0.000 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=0.311 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.311/0.311/0.311/0.000 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
Feb 19 09:38:49.261330 osdx systemd-journald[1946]: Runtime Journal (/run/log/journal/23713d8b40eb43dfbc54dc8903f4bf64) is 932.0K, max 6.5M, 5.6M free.
Feb 19 09:38:49.263694 osdx systemd-journald[1946]: Received client request to rotate journal, rotating.
Feb 19 09:38:49.263746 osdx systemd-journald[1946]: Vacuuming done, freed 0B of archived journals from /run/log/journal/23713d8b40eb43dfbc54dc8903f4bf64.
Feb 19 09:38:49.271020 osdx OSDxCLI[2298]: User 'admin' executed a new command: 'system journal clear'.
Feb 19 09:38:49.458214 osdx OSDxCLI[2298]: User 'admin' executed a new command: 'system coredump delete all'.
Feb 19 09:38:51.068870 osdx OSDxCLI[2298]: User 'admin' entered the configuration menu.
Feb 19 09:38:51.150907 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Feb 19 09:38:51.217500 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Feb 19 09:38:51.309656 osdx OSDxCLI[2298]: 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'.
Feb 19 09:38:51.384541 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Feb 19 09:38:51.491984 osdx OSDxCLI[2298]: 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'.
Feb 19 09:38:51.584236 osdx OSDxCLI[2298]: User 'admin' added a new cfg line: 'show working'.
Feb 19 09:38:51.681477 osdx ubnt-cfgd[173840]: inactive
Feb 19 09:38:51.713962 osdx INFO[173852]: FRR daemons did not change
Feb 19 09:38:51.743718 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Feb 19 09:38:51.766083 osdx (udev-worker)[173902]: Network interface NamePolicy= disabled on kernel command line.
Feb 19 09:38:51.920102 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Feb 19 09:38:51.922330 osdx cfgd[1621]: [2298]Completed change to active configuration
Feb 19 09:38:51.923808 osdx dhcpd[173979]: Wrote 0 leases to leases file.
Feb 19 09:38:51.934464 osdx OSDxCLI[2298]: User 'admin' committed the configuration.
Feb 19 09:38:51.960502 osdx OSDxCLI[2298]: User 'admin' left the configuration menu.
Feb 19 09:38:51.974928 osdx dhcpd[173979]:
Feb 19 09:38:51.974937 osdx dhcpd[173979]: No subnet declaration for eth0 (no IPv4 addresses).
Feb 19 09:38:51.974941 osdx dhcpd[173979]: ** Ignoring requests on eth0.  If this is not what
Feb 19 09:38:51.974944 osdx dhcpd[173979]:    you want, please write a subnet declaration
Feb 19 09:38:51.974947 osdx dhcpd[173979]:    in your dhcpd.conf file for the network segment
Feb 19 09:38:51.974951 osdx dhcpd[173979]:    to which interface eth0 is attached. **
Feb 19 09:38:51.974954 osdx dhcpd[173979]:
Feb 19 09:38:52.003888 osdx dhcpd[173979]: Server starting service.
Feb 19 09:38:52.689470 osdx dhcpd[173979]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Feb 19 09:38:52.833310 osdx dhcpd[173979]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Feb 19 09:38:53.690068 osdx dhcpd[173979]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Feb 19 09:38:53.690650 osdx dhcpd[173979]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Feb 19 09:38:53.728036 osdx dhcpd[173979]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Feb 19 09:38:53.833523 osdx dhcpd[173979]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Feb 19 09:38:53.834182 osdx dhcpd[173979]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Feb 19 09:38:53.848629 osdx dhcpd[173979]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2