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=0.242 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.242/0.242/0.242/0.000 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=0.549 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.549/0.549/0.549/0.000 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
Mar 23 09:42:43.273973 osdx systemd-journald[1995]: Runtime Journal (/run/log/journal/3bae93ce7bf04d9e94142a051157df70) is 928.0K, max 6.4M, 5.5M free.
Mar 23 09:42:43.277143 osdx systemd-journald[1995]: Received client request to rotate journal, rotating.
Mar 23 09:42:43.277201 osdx systemd-journald[1995]: Vacuuming done, freed 0B of archived journals from /run/log/journal/3bae93ce7bf04d9e94142a051157df70.
Mar 23 09:42:43.283369 osdx OSDxCLI[61885]: User 'admin' executed a new command: 'system journal clear'.
Mar 23 09:42:43.474070 osdx OSDxCLI[61885]: User 'admin' executed a new command: 'system coredump delete all'.
Mar 23 09:42:44.843036 osdx OSDxCLI[61885]: User 'admin' entered the configuration menu.
Mar 23 09:42:44.924156 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Mar 23 09:42:45.015463 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Mar 23 09:42:45.121783 osdx OSDxCLI[61885]: 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 23 09:42:45.182041 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Mar 23 09:42:45.292525 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'show working'.
Mar 23 09:42:45.368685 osdx ubnt-cfgd[191955]: inactive
Mar 23 09:42:45.396746 osdx INFO[191965]: FRR daemons did not change
Mar 23 09:42:45.425169 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Mar 23 09:42:45.447825 osdx (udev-worker)[192013]: Network interface NamePolicy= disabled on kernel command line.
Mar 23 09:42:45.596481 osdx dhcpd[192092]: Wrote 0 leases to leases file.
Mar 23 09:42:45.593457 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Mar 23 09:42:45.599168 osdx cfgd[1631]: [61885]Completed change to active configuration
Mar 23 09:42:45.612349 osdx OSDxCLI[61885]: User 'admin' committed the configuration.
Mar 23 09:42:45.624332 osdx dhcpd[192092]:
Mar 23 09:42:45.624507 osdx dhcpd[192092]: No subnet declaration for eth0 (no IPv4 addresses).
Mar 23 09:42:45.624560 osdx dhcpd[192092]: ** Ignoring requests on eth0.  If this is not what
Mar 23 09:42:45.624602 osdx dhcpd[192092]:    you want, please write a subnet declaration
Mar 23 09:42:45.624643 osdx dhcpd[192092]:    in your dhcpd.conf file for the network segment
Mar 23 09:42:45.624694 osdx dhcpd[192092]:    to which interface eth0 is attached. **
Mar 23 09:42:45.624738 osdx dhcpd[192092]:
Mar 23 09:42:45.633322 osdx dhcpd[192092]: Server starting service.
Mar 23 09:42:45.641004 osdx OSDxCLI[61885]: User 'admin' left the configuration menu.
Mar 23 09:42:46.389908 osdx dhcpd[192092]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Mar 23 09:42:47.390225 osdx dhcpd[192092]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Mar 23 09:42:47.390782 osdx dhcpd[192092]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Mar 23 09:42:47.424745 osdx dhcpd[192092]: 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=0.635 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.635/0.635/0.635/0.000 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=0.662 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.662/0.662/0.662/0.000 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=0.425 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.425/0.425/0.425/0.000 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
Mar 23 09:43:07.369270 osdx systemd-journald[1995]: Runtime Journal (/run/log/journal/3bae93ce7bf04d9e94142a051157df70) is 928.0K, max 6.4M, 5.5M free.
Mar 23 09:43:07.369977 osdx systemd-journald[1995]: Received client request to rotate journal, rotating.
Mar 23 09:43:07.370027 osdx systemd-journald[1995]: Vacuuming done, freed 0B of archived journals from /run/log/journal/3bae93ce7bf04d9e94142a051157df70.
Mar 23 09:43:07.380573 osdx OSDxCLI[61885]: User 'admin' executed a new command: 'system journal clear'.
Mar 23 09:43:07.603408 osdx OSDxCLI[61885]: User 'admin' executed a new command: 'system coredump delete all'.
Mar 23 09:43:09.332168 osdx OSDxCLI[61885]: User 'admin' entered the configuration menu.
Mar 23 09:43:09.432008 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Mar 23 09:43:09.571361 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Mar 23 09:43:09.696401 osdx OSDxCLI[61885]: 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 23 09:43:09.791093 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Mar 23 09:43:09.885579 osdx OSDxCLI[61885]: 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 23 09:43:09.966790 osdx OSDxCLI[61885]: User 'admin' added a new cfg line: 'show working'.
Mar 23 09:43:10.084255 osdx ubnt-cfgd[192963]: inactive
Mar 23 09:43:10.113904 osdx INFO[192975]: FRR daemons did not change
Mar 23 09:43:10.150011 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Mar 23 09:43:10.173056 osdx (udev-worker)[193025]: Network interface NamePolicy= disabled on kernel command line.
Mar 23 09:43:10.394414 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Mar 23 09:43:10.396761 osdx dhcpd[193102]: Wrote 0 leases to leases file.
Mar 23 09:43:10.399576 osdx cfgd[1631]: [61885]Completed change to active configuration
Mar 23 09:43:10.413533 osdx OSDxCLI[61885]: User 'admin' committed the configuration.
Mar 23 09:43:10.420269 osdx dhcpd[193102]:
Mar 23 09:43:10.420277 osdx dhcpd[193102]: No subnet declaration for eth0 (no IPv4 addresses).
Mar 23 09:43:10.420280 osdx dhcpd[193102]: ** Ignoring requests on eth0.  If this is not what
Mar 23 09:43:10.420282 osdx dhcpd[193102]:    you want, please write a subnet declaration
Mar 23 09:43:10.420285 osdx dhcpd[193102]:    in your dhcpd.conf file for the network segment
Mar 23 09:43:10.420287 osdx dhcpd[193102]:    to which interface eth0 is attached. **
Mar 23 09:43:10.420290 osdx dhcpd[193102]:
Mar 23 09:43:10.431323 osdx OSDxCLI[61885]: User 'admin' left the configuration menu.
Mar 23 09:43:10.438217 osdx dhcpd[193102]: Server starting service.
Mar 23 09:43:11.391066 osdx dhcpd[193102]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Mar 23 09:43:11.558426 osdx dhcpd[193102]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Mar 23 09:43:12.391822 osdx dhcpd[193102]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 23 09:43:12.392551 osdx dhcpd[193102]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 23 09:43:12.408502 osdx dhcpd[193102]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Mar 23 09:43:12.558681 osdx dhcpd[193102]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Mar 23 09:43:12.559409 osdx dhcpd[193102]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Mar 23 09:43:12.570193 osdx dhcpd[193102]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2