Relay

Contents

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.

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=0.201 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.201/0.201/0.201/0.000 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=0.235 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.235/0.235/0.235/0.000 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

Aug 20 10:24:54.295152 osdx systemd-journald[1745]: Runtime Journal (/run/log/journal/f1f2085982c441e58ba58c498ad9816b) is 1.0M, max 7.2M, 6.2M free.
Aug 20 10:24:54.298859 osdx systemd-journald[1745]: Received client request to rotate journal, rotating.
Aug 20 10:24:54.298923 osdx systemd-journald[1745]: Vacuuming done, freed 0B of archived journals from /run/log/journal/f1f2085982c441e58ba58c498ad9816b.
Aug 20 10:24:54.305873 osdx OSDxCLI[2016]: User 'admin' executed a new command: 'system journal clear'.
Aug 20 10:24:54.513058 osdx OSDxCLI[2016]: User 'admin' executed a new command: 'system coredump delete all'.
Aug 20 10:24:55.899689 osdx OSDxCLI[2016]: User 'admin' entered the configuration menu.
Aug 20 10:24:55.991489 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Aug 20 10:24:56.075975 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Aug 20 10:24:56.134664 osdx OSDxCLI[2016]: 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'.
Aug 20 10:24:56.226989 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Aug 20 10:24:56.303396 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'show working'.
Aug 20 10:24:56.399981 osdx ubnt-cfgd[65391]: inactive
Aug 20 10:24:56.428096 osdx INFO[65401]: FRR daemons did not change
Aug 20 10:24:56.454880 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Aug 20 10:24:56.474775 osdx (udev-worker)[65448]: Network interface NamePolicy= disabled on kernel command line.
Aug 20 10:24:56.639200 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Aug 20 10:24:56.641870 osdx cfgd[1447]: [2016]Completed change to active configuration
Aug 20 10:24:56.643818 osdx dhcpd[65522]: Wrote 0 leases to leases file.
Aug 20 10:24:56.655931 osdx OSDxCLI[2016]: User 'admin' committed the configuration.
Aug 20 10:24:56.661107 osdx dhcpd[65522]:
Aug 20 10:24:56.661113 osdx dhcpd[65522]: No subnet declaration for eth0 (no IPv4 addresses).
Aug 20 10:24:56.661116 osdx dhcpd[65522]: ** Ignoring requests on eth0.  If this is not what
Aug 20 10:24:56.661119 osdx dhcpd[65522]:    you want, please write a subnet declaration
Aug 20 10:24:56.661122 osdx dhcpd[65522]:    in your dhcpd.conf file for the network segment
Aug 20 10:24:56.661126 osdx dhcpd[65522]:    to which interface eth0 is attached. **
Aug 20 10:24:56.661128 osdx dhcpd[65522]:
Aug 20 10:24:56.679103 osdx dhcpd[65522]: Server starting service.
Aug 20 10:24:56.685480 osdx OSDxCLI[2016]: User 'admin' left the configuration menu.
Aug 20 10:24:57.381642 osdx dhcpd[65522]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Aug 20 10:24:58.382143 osdx dhcpd[65522]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Aug 20 10:24:58.382759 osdx dhcpd[65522]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Aug 20 10:24:58.418724 osdx dhcpd[65522]: 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=0.261 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.261/0.261/0.261/0.000 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=0.231 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.231/0.231/0.231/0.000 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

Aug 20 10:25:18.274443 osdx systemd-journald[1745]: Runtime Journal (/run/log/journal/f1f2085982c441e58ba58c498ad9816b) is 1.0M, max 7.2M, 6.2M free.
Aug 20 10:25:18.274790 osdx systemd-journald[1745]: Received client request to rotate journal, rotating.
Aug 20 10:25:18.274823 osdx systemd-journald[1745]: Vacuuming done, freed 0B of archived journals from /run/log/journal/f1f2085982c441e58ba58c498ad9816b.
Aug 20 10:25:18.283974 osdx OSDxCLI[2016]: User 'admin' executed a new command: 'system journal clear'.
Aug 20 10:25:18.495787 osdx OSDxCLI[2016]: User 'admin' executed a new command: 'system coredump delete all'.
Aug 20 10:25:20.164720 osdx OSDxCLI[2016]: User 'admin' entered the configuration menu.
Aug 20 10:25:20.242393 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Aug 20 10:25:20.331635 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Aug 20 10:25:20.393116 osdx OSDxCLI[2016]: 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'.
Aug 20 10:25:20.493680 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Aug 20 10:25:20.568193 osdx OSDxCLI[2016]: 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'.
Aug 20 10:25:20.680217 osdx OSDxCLI[2016]: User 'admin' added a new cfg line: 'show working'.
Aug 20 10:25:20.808857 osdx ubnt-cfgd[66342]: inactive
Aug 20 10:25:20.836487 osdx INFO[66354]: FRR daemons did not change
Aug 20 10:25:20.854716 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Aug 20 10:25:20.876199 osdx (udev-worker)[66402]: Network interface NamePolicy= disabled on kernel command line.
Aug 20 10:25:21.031067 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Aug 20 10:25:21.035098 osdx cfgd[1447]: [2016]Completed change to active configuration
Aug 20 10:25:21.038642 osdx dhcpd[66475]: Wrote 0 leases to leases file.
Aug 20 10:25:21.047409 osdx OSDxCLI[2016]: User 'admin' committed the configuration.
Aug 20 10:25:21.069011 osdx dhcpd[66475]:
Aug 20 10:25:21.069018 osdx dhcpd[66475]: No subnet declaration for eth0 (no IPv4 addresses).
Aug 20 10:25:21.069021 osdx dhcpd[66475]: ** Ignoring requests on eth0.  If this is not what
Aug 20 10:25:21.069024 osdx dhcpd[66475]:    you want, please write a subnet declaration
Aug 20 10:25:21.069028 osdx dhcpd[66475]:    in your dhcpd.conf file for the network segment
Aug 20 10:25:21.069031 osdx dhcpd[66475]:    to which interface eth0 is attached. **
Aug 20 10:25:21.069034 osdx dhcpd[66475]:
Aug 20 10:25:21.082642 osdx OSDxCLI[2016]: User 'admin' left the configuration menu.
Aug 20 10:25:21.090877 osdx dhcpd[66475]: Server starting service.
Aug 20 10:25:21.769531 osdx dhcpd[66475]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Aug 20 10:25:21.897257 osdx dhcpd[66475]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Aug 20 10:25:22.770005 osdx dhcpd[66475]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Aug 20 10:25:22.770595 osdx dhcpd[66475]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Aug 20 10:25:22.782533 osdx dhcpd[66475]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Aug 20 10:25:22.897462 osdx dhcpd[66475]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Aug 20 10:25:22.898032 osdx dhcpd[66475]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Aug 20 10:25:22.914060 osdx dhcpd[66475]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2

---