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=0.228 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
    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=0.242 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

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 23 07:43:37.305089 osdx systemd-journald[1537]: Runtime Journal (/run/log/journal/904066e2ce1346e1b59b092eb2722774) is 1.0M, max 7.2M, 6.1M free.
Jun 23 07:43:37.308418 osdx systemd-journald[1537]: Received client request to rotate journal, rotating.
Jun 23 07:43:37.308476 osdx systemd-journald[1537]: Vacuuming done, freed 0B of archived journals from /run/log/journal/904066e2ce1346e1b59b092eb2722774.
Jun 23 07:43:37.316499 osdx OSDxCLI[1792]: User 'admin' executed a new command: 'system journal clear'.
Jun 23 07:43:37.522112 osdx OSDxCLI[1792]: User 'admin' executed a new command: 'system coredump delete all'.
Jun 23 07:43:38.894938 osdx OSDxCLI[1792]: User 'admin' entered the configuration menu.
Jun 23 07:43:38.972281 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Jun 23 07:43:39.058386 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Jun 23 07:43:39.122114 osdx OSDxCLI[1792]: 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 23 07:43:39.246218 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Jun 23 07:43:39.322208 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'show working'.
Jun 23 07:43:39.430473 osdx INFO[37593]: FRR daemons did not change
Jun 23 07:43:39.448413 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Jun 23 07:43:39.474193 osdx (udev-worker)[37643]: Network interface NamePolicy= disabled on kernel command line.
Jun 23 07:43:39.592987 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Jun 23 07:43:39.594948 osdx cfgd[1243]: [1792]Completed change to active configuration
Jun 23 07:43:39.595955 osdx dhcpd[37667]: Wrote 0 leases to leases file.
Jun 23 07:43:39.617259 osdx dhcpd[37667]:
Jun 23 07:43:39.617267 osdx dhcpd[37667]: No subnet declaration for eth0 (no IPv4 addresses).
Jun 23 07:43:39.617269 osdx dhcpd[37667]: ** Ignoring requests on eth0.  If this is not what
Jun 23 07:43:39.617271 osdx dhcpd[37667]:    you want, please write a subnet declaration
Jun 23 07:43:39.617274 osdx dhcpd[37667]:    in your dhcpd.conf file for the network segment
Jun 23 07:43:39.617276 osdx dhcpd[37667]:    to which interface eth0 is attached. **
Jun 23 07:43:39.617278 osdx dhcpd[37667]:
Jun 23 07:43:39.624010 osdx OSDxCLI[1792]: User 'admin' committed the configuration.
Jun 23 07:43:39.632547 osdx dhcpd[37667]: Server starting service.
Jun 23 07:43:39.641353 osdx OSDxCLI[1792]: User 'admin' left the configuration menu.
Jun 23 07:43:40.246267 osdx dhcpd[37667]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Jun 23 07:43:41.246801 osdx dhcpd[37667]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Jun 23 07:43:41.248102 osdx dhcpd[37667]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Jun 23 07:43:41.267186 osdx dhcpd[37667]: 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=0.215 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.215/0.215/0.215/0.000 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=0.274 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.274/0.274/0.274/0.000 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=0.236 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.236/0.236/0.236/0.000 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
Jun 23 07:44:09.271696 osdx systemd-journald[1537]: Runtime Journal (/run/log/journal/904066e2ce1346e1b59b092eb2722774) is 1020.0K, max 7.2M, 6.2M free.
Jun 23 07:44:09.274785 osdx systemd-journald[1537]: Received client request to rotate journal, rotating.
Jun 23 07:44:09.274834 osdx systemd-journald[1537]: Vacuuming done, freed 0B of archived journals from /run/log/journal/904066e2ce1346e1b59b092eb2722774.
Jun 23 07:44:09.281992 osdx OSDxCLI[1792]: User 'admin' executed a new command: 'system journal clear'.
Jun 23 07:44:09.480071 osdx OSDxCLI[1792]: User 'admin' executed a new command: 'system coredump delete all'.
Jun 23 07:44:11.003736 osdx OSDxCLI[1792]: User 'admin' entered the configuration menu.
Jun 23 07:44:11.082926 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Jun 23 07:44:11.162737 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Jun 23 07:44:11.223908 osdx OSDxCLI[1792]: 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 23 07:44:11.328006 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Jun 23 07:44:11.389262 osdx OSDxCLI[1792]: 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 23 07:44:11.506851 osdx OSDxCLI[1792]: User 'admin' added a new cfg line: 'show working'.
Jun 23 07:44:11.594633 osdx INFO[38259]: FRR daemons did not change
Jun 23 07:44:11.618798 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Jun 23 07:44:11.646969 osdx (udev-worker)[38311]: Network interface NamePolicy= disabled on kernel command line.
Jun 23 07:44:11.763166 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Jun 23 07:44:11.764926 osdx cfgd[1243]: [1792]Completed change to active configuration
Jun 23 07:44:11.767465 osdx dhcpd[38332]: Wrote 0 leases to leases file.
Jun 23 07:44:11.785104 osdx dhcpd[38332]:
Jun 23 07:44:11.785111 osdx dhcpd[38332]: No subnet declaration for eth0 (no IPv4 addresses).
Jun 23 07:44:11.785115 osdx dhcpd[38332]: ** Ignoring requests on eth0.  If this is not what
Jun 23 07:44:11.785117 osdx dhcpd[38332]:    you want, please write a subnet declaration
Jun 23 07:44:11.785120 osdx dhcpd[38332]:    in your dhcpd.conf file for the network segment
Jun 23 07:44:11.785123 osdx dhcpd[38332]:    to which interface eth0 is attached. **
Jun 23 07:44:11.785125 osdx dhcpd[38332]:
Jun 23 07:44:11.792525 osdx OSDxCLI[1792]: User 'admin' committed the configuration.
Jun 23 07:44:11.802886 osdx dhcpd[38332]: Server starting service.
Jun 23 07:44:11.808447 osdx OSDxCLI[1792]: User 'admin' left the configuration menu.
Jun 23 07:44:12.504617 osdx dhcpd[38332]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Jun 23 07:44:12.664328 osdx dhcpd[38332]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Jun 23 07:44:13.505090 osdx dhcpd[38332]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jun 23 07:44:13.505759 osdx dhcpd[38332]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jun 23 07:44:13.521528 osdx dhcpd[38332]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jun 23 07:44:13.664576 osdx dhcpd[38332]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Jun 23 07:44:13.665240 osdx dhcpd[38332]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Jun 23 07:44:13.682207 osdx dhcpd[38332]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2