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=0.237 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.237/0.237/0.237/0.000 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=0.175 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.175/0.175/0.175/0.000 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
Mar 24 12:56:41.269047 osdx systemd-journald[1562]: Runtime Journal (/run/log/journal/4697983b28394fbab81ced9284dd096a) is 1016.0K, max 6.5M, 5.5M free.
Mar 24 12:56:41.272088 osdx systemd-journald[1562]: Received client request to rotate journal, rotating.
Mar 24 12:56:41.272144 osdx systemd-journald[1562]: Vacuuming done, freed 0B of archived journals from /run/log/journal/4697983b28394fbab81ced9284dd096a.
Mar 24 12:56:41.279672 osdx OSDxCLI[198564]: User 'admin' executed a new command: 'system journal clear'.
Mar 24 12:56:41.474927 osdx OSDxCLI[198564]: User 'admin' executed a new command: 'system coredump delete all'.
Mar 24 12:56:42.734263 osdx OSDxCLI[198564]: User 'admin' entered the configuration menu.
Mar 24 12:56:42.810971 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Mar 24 12:56:42.900820 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Mar 24 12:56:42.960824 osdx OSDxCLI[198564]: 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 24 12:56:43.053571 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Mar 24 12:56:43.121799 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'show working'.
Mar 24 12:56:43.218557 osdx ubnt-cfgd[300355]: inactive
Mar 24 12:56:43.242624 osdx INFO[300365]: FRR daemons did not change
Mar 24 12:56:43.264086 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Mar 24 12:56:43.282531 osdx (udev-worker)[300412]: Network interface NamePolicy= disabled on kernel command line.
Mar 24 12:56:43.408384 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Mar 24 12:56:43.411047 osdx cfgd[1263]: [198564]Completed change to active configuration
Mar 24 12:56:43.412330 osdx dhcpd[300486]: Wrote 0 leases to leases file.
Mar 24 12:56:43.425357 osdx OSDxCLI[198564]: User 'admin' committed the configuration.
Mar 24 12:56:43.437162 osdx dhcpd[300486]:
Mar 24 12:56:43.437169 osdx dhcpd[300486]: No subnet declaration for eth0 (no IPv4 addresses).
Mar 24 12:56:43.437172 osdx dhcpd[300486]: ** Ignoring requests on eth0.  If this is not what
Mar 24 12:56:43.437174 osdx dhcpd[300486]:    you want, please write a subnet declaration
Mar 24 12:56:43.437177 osdx dhcpd[300486]:    in your dhcpd.conf file for the network segment
Mar 24 12:56:43.437179 osdx dhcpd[300486]:    to which interface eth0 is attached. **
Mar 24 12:56:43.437182 osdx dhcpd[300486]:
Mar 24 12:56:43.441589 osdx OSDxCLI[198564]: User 'admin' left the configuration menu.
Mar 24 12:56:43.444158 osdx dhcpd[300486]: Server starting service.
Mar 24 12:56:44.006230 osdx dhcpd[300486]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Mar 24 12:56:45.006772 osdx dhcpd[300486]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Mar 24 12:56:45.007393 osdx dhcpd[300486]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Mar 24 12:56:45.047572 osdx dhcpd[300486]: 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=0.300 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.300/0.300/0.300/0.000 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=0.164 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.164/0.164/0.164/0.000 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
Mar 24 12:57:04.287137 osdx systemd-journald[1562]: Runtime Journal (/run/log/journal/4697983b28394fbab81ced9284dd096a) is 932.0K, max 6.5M, 5.6M free.
Mar 24 12:57:04.290088 osdx systemd-journald[1562]: Received client request to rotate journal, rotating.
Mar 24 12:57:04.290156 osdx systemd-journald[1562]: Vacuuming done, freed 0B of archived journals from /run/log/journal/4697983b28394fbab81ced9284dd096a.
Mar 24 12:57:04.296874 osdx OSDxCLI[198564]: User 'admin' executed a new command: 'system journal clear'.
Mar 24 12:57:04.499885 osdx OSDxCLI[198564]: User 'admin' executed a new command: 'system coredump delete all'.
Mar 24 12:57:06.122268 osdx OSDxCLI[198564]: User 'admin' entered the configuration menu.
Mar 24 12:57:06.202239 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Mar 24 12:57:06.281508 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Mar 24 12:57:06.349824 osdx OSDxCLI[198564]: 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 24 12:57:06.454934 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Mar 24 12:57:06.524322 osdx OSDxCLI[198564]: 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 24 12:57:06.637689 osdx OSDxCLI[198564]: User 'admin' added a new cfg line: 'show working'.
Mar 24 12:57:06.703719 osdx ubnt-cfgd[301302]: inactive
Mar 24 12:57:06.730481 osdx INFO[301314]: FRR daemons did not change
Mar 24 12:57:06.750093 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Mar 24 12:57:06.767287 osdx (udev-worker)[301362]: Network interface NamePolicy= disabled on kernel command line.
Mar 24 12:57:06.934386 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Mar 24 12:57:06.936209 osdx cfgd[1263]: [198564]Completed change to active configuration
Mar 24 12:57:06.941575 osdx dhcpd[301435]: Wrote 0 leases to leases file.
Mar 24 12:57:06.948045 osdx OSDxCLI[198564]: User 'admin' committed the configuration.
Mar 24 12:57:06.993920 osdx dhcpd[301435]:
Mar 24 12:57:06.993925 osdx dhcpd[301435]: No subnet declaration for eth0 (no IPv4 addresses).
Mar 24 12:57:06.993927 osdx dhcpd[301435]: ** Ignoring requests on eth0.  If this is not what
Mar 24 12:57:06.993930 osdx dhcpd[301435]:    you want, please write a subnet declaration
Mar 24 12:57:06.993932 osdx dhcpd[301435]:    in your dhcpd.conf file for the network segment
Mar 24 12:57:06.993935 osdx dhcpd[301435]:    to which interface eth0 is attached. **
Mar 24 12:57:06.993937 osdx dhcpd[301435]:
Mar 24 12:57:06.996282 osdx OSDxCLI[198564]: User 'admin' left the configuration menu.
Mar 24 12:57:07.006222 osdx dhcpd[301435]: Server starting service.
Mar 24 12:57:07.632190 osdx dhcpd[301435]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Mar 24 12:57:07.775921 osdx dhcpd[301435]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Mar 24 12:57:08.632777 osdx dhcpd[301435]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 24 12:57:08.633379 osdx dhcpd[301435]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 24 12:57:08.662098 osdx dhcpd[301435]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 24 12:57:08.776136 osdx dhcpd[301435]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Mar 24 12:57:08.776748 osdx dhcpd[301435]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Mar 24 12:57:08.799360 osdx dhcpd[301435]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2