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=0.257 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.257/0.257/0.257/0.000 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=0.247 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.247/0.247/0.247/0.000 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
Jun 02 09:45:22.304520 osdx systemd-journald[1765]: Runtime Journal (/run/log/journal/27bca15c163b4997962c56740a934d39) is 932.0K, max 6.5M, 5.6M free.
Jun 02 09:45:22.307104 osdx systemd-journald[1765]: Received client request to rotate journal, rotating.
Jun 02 09:45:22.307177 osdx systemd-journald[1765]: Vacuuming done, freed 0B of archived journals from /run/log/journal/27bca15c163b4997962c56740a934d39.
Jun 02 09:45:22.316423 osdx OSDxCLI[68402]: User 'admin' executed a new command: 'system journal clear'.
Jun 02 09:45:22.568989 osdx OSDxCLI[68402]: User 'admin' executed a new command: 'system coredump delete all'.
Jun 02 09:45:24.470437 osdx OSDxCLI[68402]: User 'admin' entered the configuration menu.
Jun 02 09:45:24.621468 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Jun 02 09:45:24.701224 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Jun 02 09:45:24.790566 osdx OSDxCLI[68402]: 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'.
Jun 02 09:45:24.907414 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Jun 02 09:45:24.992080 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'show working'.
Jun 02 09:45:25.092423 osdx ubnt-cfgd[146473]: inactive
Jun 02 09:45:25.200197 osdx INFO[146483]: FRR daemons did not change
Jun 02 09:45:25.243112 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Jun 02 09:45:25.262885 osdx (udev-worker)[146534]: Network interface NamePolicy= disabled on kernel command line.
Jun 02 09:45:25.475715 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Jun 02 09:45:25.479189 osdx cfgd[1460]: [68402]Completed change to active configuration
Jun 02 09:45:25.480712 osdx dhcpd[146606]: Wrote 0 leases to leases file.
Jun 02 09:45:25.495149 osdx OSDxCLI[68402]: User 'admin' committed the configuration.
Jun 02 09:45:25.508252 osdx dhcpd[146606]:
Jun 02 09:45:25.508259 osdx dhcpd[146606]: No subnet declaration for eth0 (no IPv4 addresses).
Jun 02 09:45:25.508263 osdx dhcpd[146606]: ** Ignoring requests on eth0.  If this is not what
Jun 02 09:45:25.508266 osdx dhcpd[146606]:    you want, please write a subnet declaration
Jun 02 09:45:25.508268 osdx dhcpd[146606]:    in your dhcpd.conf file for the network segment
Jun 02 09:45:25.508270 osdx dhcpd[146606]:    to which interface eth0 is attached. **
Jun 02 09:45:25.508273 osdx dhcpd[146606]:
Jun 02 09:45:25.520089 osdx OSDxCLI[68402]: User 'admin' left the configuration menu.
Jun 02 09:45:25.523232 osdx dhcpd[146606]: Server starting service.
Jun 02 09:45:26.299253 osdx dhcpd[146606]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Jun 02 09:45:27.299943 osdx dhcpd[146606]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Jun 02 09:45:27.300699 osdx dhcpd[146606]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Jun 02 09:45:27.319186 osdx dhcpd[146606]: 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=0.239 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.239/0.239/0.239/0.000 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=0.305 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.305/0.305/0.305/0.000 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=0.225 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.225/0.225/0.225/0.000 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  fe80::dcad:beff:feef:6c20/64  up     up
    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
Jun 02 09:45:59.282905 osdx systemd-journald[1765]: Runtime Journal (/run/log/journal/27bca15c163b4997962c56740a934d39) is 932.0K, max 6.5M, 5.6M free.
Jun 02 09:45:59.285799 osdx systemd-journald[1765]: Received client request to rotate journal, rotating.
Jun 02 09:45:59.285855 osdx systemd-journald[1765]: Vacuuming done, freed 0B of archived journals from /run/log/journal/27bca15c163b4997962c56740a934d39.
Jun 02 09:45:59.292350 osdx OSDxCLI[68402]: User 'admin' executed a new command: 'system journal clear'.
Jun 02 09:45:59.518650 osdx OSDxCLI[68402]: User 'admin' executed a new command: 'system coredump delete all'.
Jun 02 09:46:01.167557 osdx OSDxCLI[68402]: User 'admin' entered the configuration menu.
Jun 02 09:46:01.319742 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Jun 02 09:46:01.409645 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Jun 02 09:46:01.482397 osdx OSDxCLI[68402]: 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'.
Jun 02 09:46:01.582654 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Jun 02 09:46:01.645046 osdx OSDxCLI[68402]: 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'.
Jun 02 09:46:01.751069 osdx OSDxCLI[68402]: User 'admin' added a new cfg line: 'show working'.
Jun 02 09:46:01.810614 osdx ubnt-cfgd[147426]: inactive
Jun 02 09:46:01.844207 osdx INFO[147438]: FRR daemons did not change
Jun 02 09:46:01.877778 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Jun 02 09:46:01.894961 osdx (udev-worker)[147488]: Network interface NamePolicy= disabled on kernel command line.
Jun 02 09:46:02.590292 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Jun 02 09:46:02.592752 osdx cfgd[1460]: [68402]Completed change to active configuration
Jun 02 09:46:02.593572 osdx dhcpd[147561]: Wrote 0 leases to leases file.
Jun 02 09:46:02.605197 osdx OSDxCLI[68402]: User 'admin' committed the configuration.
Jun 02 09:46:02.622663 osdx OSDxCLI[68402]: User 'admin' left the configuration menu.
Jun 02 09:46:03.956902 osdx dhcpd[147561]:
Jun 02 09:46:03.956907 osdx dhcpd[147561]: No subnet declaration for eth0 (no IPv4 addresses).
Jun 02 09:46:03.956912 osdx dhcpd[147561]: ** Ignoring requests on eth0.  If this is not what
Jun 02 09:46:03.956914 osdx dhcpd[147561]:    you want, please write a subnet declaration
Jun 02 09:46:03.956917 osdx dhcpd[147561]:    in your dhcpd.conf file for the network segment
Jun 02 09:46:03.956919 osdx dhcpd[147561]:    to which interface eth0 is attached. **
Jun 02 09:46:03.956922 osdx dhcpd[147561]:
Jun 02 09:46:03.969921 osdx dhcpd[147561]: Server starting service.
Jun 02 09:46:09.038384 osdx dhcpd[147561]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Jun 02 09:46:09.592406 osdx dhcpd[147561]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Jun 02 09:46:10.038629 osdx dhcpd[147561]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jun 02 09:46:10.039809 osdx dhcpd[147561]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jun 02 09:46:10.074097 osdx dhcpd[147561]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jun 02 09:46:10.592607 osdx dhcpd[147561]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Jun 02 09:46:10.593258 osdx dhcpd[147561]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Jun 02 09:46:10.634025 osdx dhcpd[147561]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2