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=0.238 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.238/0.238/0.238/0.000 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=0.248 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.248/0.248/0.248/0.000 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
Dec 17 21:25:36.371723 osdx systemd-journald[1556]: Runtime Journal (/run/log/journal/c6a6a8e2d9d640e4bbdbbcec0635592c) is 932.0K, max 6.5M, 5.6M free.
Dec 17 21:25:36.374523 osdx systemd-journald[1556]: Received client request to rotate journal, rotating.
Dec 17 21:25:36.374591 osdx systemd-journald[1556]: Vacuuming done, freed 0B of archived journals from /run/log/journal/c6a6a8e2d9d640e4bbdbbcec0635592c.
Dec 17 21:25:36.384982 osdx OSDxCLI[67921]: User 'admin' executed a new command: 'system journal clear'.
Dec 17 21:25:36.621528 osdx OSDxCLI[67921]: User 'admin' executed a new command: 'system coredump delete all'.
Dec 17 21:25:38.080385 osdx OSDxCLI[67921]: User 'admin' entered the configuration menu.
Dec 17 21:25:38.158358 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Dec 17 21:25:38.241243 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Dec 17 21:25:38.317175 osdx OSDxCLI[67921]: 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'.
Dec 17 21:25:38.434319 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Dec 17 21:25:38.506890 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'show working'.
Dec 17 21:25:38.635106 osdx ubnt-cfgd[266096]: inactive
Dec 17 21:25:38.667462 osdx INFO[266106]: FRR daemons did not change
Dec 17 21:25:38.694504 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Dec 17 21:25:38.715116 osdx (udev-worker)[266154]: Network interface NamePolicy= disabled on kernel command line.
Dec 17 21:25:38.859201 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Dec 17 21:25:38.861945 osdx cfgd[1255]: [67921]Completed change to active configuration
Dec 17 21:25:38.862312 osdx dhcpd[266227]: Wrote 0 leases to leases file.
Dec 17 21:25:38.875834 osdx OSDxCLI[67921]: User 'admin' committed the configuration.
Dec 17 21:25:38.885934 osdx dhcpd[266227]:
Dec 17 21:25:38.885942 osdx dhcpd[266227]: No subnet declaration for eth0 (no IPv4 addresses).
Dec 17 21:25:38.885944 osdx dhcpd[266227]: ** Ignoring requests on eth0.  If this is not what
Dec 17 21:25:38.885947 osdx dhcpd[266227]:    you want, please write a subnet declaration
Dec 17 21:25:38.885949 osdx dhcpd[266227]:    in your dhcpd.conf file for the network segment
Dec 17 21:25:38.885951 osdx dhcpd[266227]:    to which interface eth0 is attached. **
Dec 17 21:25:38.885953 osdx dhcpd[266227]:
Dec 17 21:25:38.892692 osdx OSDxCLI[67921]: User 'admin' left the configuration menu.
Dec 17 21:25:38.898686 osdx dhcpd[266227]: Server starting service.
Dec 17 21:25:39.518627 osdx dhcpd[266227]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Dec 17 21:25:40.518927 osdx dhcpd[266227]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Dec 17 21:25:40.519834 osdx dhcpd[266227]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Dec 17 21:25:40.539729 osdx dhcpd[266227]: 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=0.254 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.254/0.254/0.254/0.000 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=0.283 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.283/0.283/0.283/0.000 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=0.260 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.260/0.260/0.260/0.000 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
Dec 17 21:26:02.283668 osdx systemd-journald[1556]: Runtime Journal (/run/log/journal/c6a6a8e2d9d640e4bbdbbcec0635592c) is 932.0K, max 6.5M, 5.6M free.
Dec 17 21:26:02.285363 osdx systemd-journald[1556]: Received client request to rotate journal, rotating.
Dec 17 21:26:02.285431 osdx systemd-journald[1556]: Vacuuming done, freed 0B of archived journals from /run/log/journal/c6a6a8e2d9d640e4bbdbbcec0635592c.
Dec 17 21:26:02.294108 osdx OSDxCLI[67921]: User 'admin' executed a new command: 'system journal clear'.
Dec 17 21:26:02.485775 osdx OSDxCLI[67921]: User 'admin' executed a new command: 'system coredump delete all'.
Dec 17 21:26:04.032329 osdx OSDxCLI[67921]: User 'admin' entered the configuration menu.
Dec 17 21:26:04.137857 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Dec 17 21:26:04.223773 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Dec 17 21:26:04.320539 osdx OSDxCLI[67921]: 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'.
Dec 17 21:26:04.382211 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Dec 17 21:26:04.557580 osdx OSDxCLI[67921]: 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'.
Dec 17 21:26:04.635527 osdx OSDxCLI[67921]: User 'admin' added a new cfg line: 'show working'.
Dec 17 21:26:04.811567 osdx ubnt-cfgd[267053]: inactive
Dec 17 21:26:04.891155 osdx INFO[267065]: FRR daemons did not change
Dec 17 21:26:04.913353 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Dec 17 21:26:04.938096 osdx (udev-worker)[267114]: Network interface NamePolicy= disabled on kernel command line.
Dec 17 21:26:05.213977 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Dec 17 21:26:05.218089 osdx cfgd[1255]: [67921]Completed change to active configuration
Dec 17 21:26:05.231434 osdx dhcpd[267186]: Wrote 0 leases to leases file.
Dec 17 21:26:05.233536 osdx OSDxCLI[67921]: User 'admin' committed the configuration.
Dec 17 21:26:05.259983 osdx OSDxCLI[67921]: User 'admin' left the configuration menu.
Dec 17 21:26:05.262155 osdx dhcpd[267186]:
Dec 17 21:26:05.262162 osdx dhcpd[267186]: No subnet declaration for eth0 (no IPv4 addresses).
Dec 17 21:26:05.262164 osdx dhcpd[267186]: ** Ignoring requests on eth0.  If this is not what
Dec 17 21:26:05.262167 osdx dhcpd[267186]:    you want, please write a subnet declaration
Dec 17 21:26:05.262169 osdx dhcpd[267186]:    in your dhcpd.conf file for the network segment
Dec 17 21:26:05.262171 osdx dhcpd[267186]:    to which interface eth0 is attached. **
Dec 17 21:26:05.262173 osdx dhcpd[267186]:
Dec 17 21:26:05.281477 osdx dhcpd[267186]: Server starting service.
Dec 17 21:26:06.066102 osdx dhcpd[267186]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Dec 17 21:26:06.229354 osdx dhcpd[267186]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Dec 17 21:26:07.066841 osdx dhcpd[267186]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Dec 17 21:26:07.068327 osdx dhcpd[267186]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Dec 17 21:26:07.090403 osdx dhcpd[267186]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Dec 17 21:26:07.229637 osdx dhcpd[267186]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Dec 17 21:26:07.230339 osdx dhcpd[267186]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Dec 17 21:26:07.261836 osdx dhcpd[267186]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2