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=0.226 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.226/0.226/0.226/0.000 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

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=0.292 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.292/0.292/0.292/0.000 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

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
Oct 20 16:05:51.340782 osdx systemd-journald[1753]: Runtime Journal (/run/log/journal/4442b1c48b0b445ebeebca784f5233e7) is 932.0K, max 6.5M, 5.6M free.
Oct 20 16:05:51.342235 osdx systemd-journald[1753]: Received client request to rotate journal, rotating.
Oct 20 16:05:51.342299 osdx systemd-journald[1753]: Vacuuming done, freed 0B of archived journals from /run/log/journal/4442b1c48b0b445ebeebca784f5233e7.
Oct 20 16:05:51.353946 osdx OSDxCLI[216315]: User 'admin' executed a new command: 'system journal clear'.
Oct 20 16:05:51.555422 osdx OSDxCLI[216315]: User 'admin' executed a new command: 'system coredump delete all'.
Oct 20 16:05:52.976554 osdx OSDxCLI[216315]: User 'admin' entered the configuration menu.
Oct 20 16:05:53.115122 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Oct 20 16:05:53.172456 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Oct 20 16:05:53.273911 osdx OSDxCLI[216315]: 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'.
Oct 20 16:05:53.331768 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Oct 20 16:05:53.454654 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'show working'.
Oct 20 16:05:53.526924 osdx ubnt-cfgd[254271]: inactive
Oct 20 16:05:53.550742 osdx INFO[254281]: FRR daemons did not change
Oct 20 16:05:53.570237 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Oct 20 16:05:53.587082 osdx (udev-worker)[254330]: Network interface NamePolicy= disabled on kernel command line.
Oct 20 16:05:53.722671 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Oct 20 16:05:53.725034 osdx dhcpd[254402]: Wrote 0 leases to leases file.
Oct 20 16:05:53.725550 osdx cfgd[1444]: [216315]Completed change to active configuration
Oct 20 16:05:53.736542 osdx OSDxCLI[216315]: User 'admin' committed the configuration.
Oct 20 16:05:53.767054 osdx OSDxCLI[216315]: User 'admin' left the configuration menu.
Oct 20 16:05:53.768372 osdx dhcpd[254402]:
Oct 20 16:05:53.768378 osdx dhcpd[254402]: No subnet declaration for eth0 (no IPv4 addresses).
Oct 20 16:05:53.768381 osdx dhcpd[254402]: ** Ignoring requests on eth0.  If this is not what
Oct 20 16:05:53.768383 osdx dhcpd[254402]:    you want, please write a subnet declaration
Oct 20 16:05:53.768386 osdx dhcpd[254402]:    in your dhcpd.conf file for the network segment
Oct 20 16:05:53.768388 osdx dhcpd[254402]:    to which interface eth0 is attached. **
Oct 20 16:05:53.768391 osdx dhcpd[254402]:
Oct 20 16:05:53.782409 osdx dhcpd[254402]: Server starting service.
Oct 20 16:05:54.354664 osdx dhcpd[254402]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Oct 20 16:05:55.355533 osdx dhcpd[254402]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Oct 20 16:05:55.356097 osdx dhcpd[254402]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Oct 20 16:05:55.389116 osdx dhcpd[254402]: 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=0.226 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.226/0.226/0.226/0.000 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=0.244 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.244/0.244/0.244/0.000 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

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=0.228 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.228/0.228/0.228/0.000 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

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

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
Oct 20 16:06:16.279278 osdx systemd-journald[1753]: Runtime Journal (/run/log/journal/4442b1c48b0b445ebeebca784f5233e7) is 932.0K, max 6.5M, 5.6M free.
Oct 20 16:06:16.283197 osdx systemd-journald[1753]: Received client request to rotate journal, rotating.
Oct 20 16:06:16.283264 osdx systemd-journald[1753]: Vacuuming done, freed 0B of archived journals from /run/log/journal/4442b1c48b0b445ebeebca784f5233e7.
Oct 20 16:06:16.288634 osdx OSDxCLI[216315]: User 'admin' executed a new command: 'system journal clear'.
Oct 20 16:06:16.488734 osdx OSDxCLI[216315]: User 'admin' executed a new command: 'system coredump delete all'.
Oct 20 16:06:18.106245 osdx OSDxCLI[216315]: User 'admin' entered the configuration menu.
Oct 20 16:06:18.178656 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Oct 20 16:06:18.260480 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Oct 20 16:06:18.318715 osdx OSDxCLI[216315]: 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'.
Oct 20 16:06:18.440640 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Oct 20 16:06:18.548294 osdx OSDxCLI[216315]: 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'.
Oct 20 16:06:18.610400 osdx OSDxCLI[216315]: User 'admin' added a new cfg line: 'show working'.
Oct 20 16:06:18.725025 osdx ubnt-cfgd[255222]: inactive
Oct 20 16:06:18.764682 osdx INFO[255234]: FRR daemons did not change
Oct 20 16:06:18.783218 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Oct 20 16:06:18.803574 osdx (udev-worker)[255281]: Network interface NamePolicy= disabled on kernel command line.
Oct 20 16:06:18.935781 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Oct 20 16:06:18.939332 osdx cfgd[1444]: [216315]Completed change to active configuration
Oct 20 16:06:18.940846 osdx dhcpd[255355]: Wrote 0 leases to leases file.
Oct 20 16:06:18.953291 osdx OSDxCLI[216315]: User 'admin' committed the configuration.
Oct 20 16:06:18.970254 osdx OSDxCLI[216315]: User 'admin' left the configuration menu.
Oct 20 16:06:18.971573 osdx dhcpd[255355]:
Oct 20 16:06:18.971577 osdx dhcpd[255355]: No subnet declaration for eth0 (no IPv4 addresses).
Oct 20 16:06:18.971580 osdx dhcpd[255355]: ** Ignoring requests on eth0.  If this is not what
Oct 20 16:06:18.971582 osdx dhcpd[255355]:    you want, please write a subnet declaration
Oct 20 16:06:18.971584 osdx dhcpd[255355]:    in your dhcpd.conf file for the network segment
Oct 20 16:06:18.971586 osdx dhcpd[255355]:    to which interface eth0 is attached. **
Oct 20 16:06:18.971588 osdx dhcpd[255355]:
Oct 20 16:06:18.987309 osdx dhcpd[255355]: Server starting service.
Oct 20 16:06:19.751433 osdx dhcpd[255355]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Oct 20 16:06:19.863372 osdx dhcpd[255355]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Oct 20 16:06:20.752193 osdx dhcpd[255355]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Oct 20 16:06:20.752796 osdx dhcpd[255355]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Oct 20 16:06:20.788965 osdx dhcpd[255355]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Oct 20 16:06:20.863509 osdx dhcpd[255355]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Oct 20 16:06:20.864043 osdx dhcpd[255355]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Oct 20 16:06:20.874394 osdx dhcpd[255355]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2