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=0.184 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.184/0.184/0.184/0.000 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=0.203 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.203/0.203/0.203/0.000 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
Jan 10 13:47:45.270213 osdx systemd-journald[1523]: Runtime Journal (/run/log/journal/7179cccd71d140d8bcd6364001e8f483) is 1.0M, max 7.2M, 6.2M free.
Jan 10 13:47:45.274138 osdx systemd-journald[1523]: Received client request to rotate journal, rotating.
Jan 10 13:47:45.274202 osdx systemd-journald[1523]: Vacuuming done, freed 0B of archived journals from /run/log/journal/7179cccd71d140d8bcd6364001e8f483.
Jan 10 13:47:45.282039 osdx OSDxCLI[1768]: User 'admin' executed a new command: 'system journal clear'.
Jan 10 13:47:45.704261 osdx osdx-coredump[96711]: Deleting all coredumps in /opt/vyatta/etc/config/coredump...
Jan 10 13:47:45.711633 osdx OSDxCLI[1768]: User 'admin' executed a new command: 'system coredump delete all'.
Jan 10 13:47:47.093734 osdx OSDxCLI[1768]: User 'admin' entered the configuration menu.
Jan 10 13:47:47.169200 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Jan 10 13:47:47.248953 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Jan 10 13:47:47.309245 osdx OSDxCLI[1768]: 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'.
Jan 10 13:47:47.412109 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Jan 10 13:47:47.474993 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'show working'.
Jan 10 13:47:47.601936 osdx INFO[96739]: FRR daemons did not change
Jan 10 13:47:47.622153 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Jan 10 13:47:47.642623 osdx (udev-worker)[96786]: Network interface NamePolicy= disabled on kernel command line.
Jan 10 13:47:47.778408 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Jan 10 13:47:47.780071 osdx cfgd[1231]: [1768]Completed change to active configuration
Jan 10 13:47:47.782007 osdx dhcpd[96812]: Wrote 0 leases to leases file.
Jan 10 13:47:47.805558 osdx OSDxCLI[1768]: User 'admin' committed the configuration.
Jan 10 13:47:47.821283 osdx OSDxCLI[1768]: User 'admin' left the configuration menu.
Jan 10 13:47:47.883149 osdx dhcpd[96812]:
Jan 10 13:47:47.883154 osdx dhcpd[96812]: No subnet declaration for eth0 (no IPv4 addresses).
Jan 10 13:47:47.883157 osdx dhcpd[96812]: ** Ignoring requests on eth0.  If this is not what
Jan 10 13:47:47.883159 osdx dhcpd[96812]:    you want, please write a subnet declaration
Jan 10 13:47:47.883161 osdx dhcpd[96812]:    in your dhcpd.conf file for the network segment
Jan 10 13:47:47.883164 osdx dhcpd[96812]:    to which interface eth0 is attached. **
Jan 10 13:47:47.883166 osdx dhcpd[96812]:
Jan 10 13:47:47.906263 osdx dhcpd[96812]: Server starting service.
Jan 10 13:47:48.361122 osdx dhcpd[96812]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.3
Jan 10 13:47:49.361283 osdx dhcpd[96812]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Jan 10 13:47:49.361759 osdx dhcpd[96812]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.3
Jan 10 13:47:49.369829 osdx dhcpd[96812]: 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=0.190 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.190/0.190/0.190/0.000 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=0.181 ms

--- 1.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.181/0.181/0.181/0.000 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=0.221 ms

--- 10.0.0.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.221/0.221/0.221/0.000 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
Jan 10 13:48:07.264075 osdx systemd-journald[1523]: Runtime Journal (/run/log/journal/7179cccd71d140d8bcd6364001e8f483) is 1.0M, max 7.2M, 6.2M free.
Jan 10 13:48:07.266339 osdx systemd-journald[1523]: Received client request to rotate journal, rotating.
Jan 10 13:48:07.266384 osdx systemd-journald[1523]: Vacuuming done, freed 0B of archived journals from /run/log/journal/7179cccd71d140d8bcd6364001e8f483.
Jan 10 13:48:07.273296 osdx OSDxCLI[1768]: User 'admin' executed a new command: 'system journal clear'.
Jan 10 13:48:07.712622 osdx osdx-coredump[97407]: Deleting all coredumps in /opt/vyatta/etc/config/coredump...
Jan 10 13:48:07.720142 osdx OSDxCLI[1768]: User 'admin' executed a new command: 'system coredump delete all'.
Jan 10 13:48:09.345988 osdx OSDxCLI[1768]: User 'admin' entered the configuration menu.
Jan 10 13:48:09.416467 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'set interfaces eth0.100 address 10.0.0.1/24'.
Jan 10 13:48:09.498405 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'set service dhcp-server shared-network dummy subnet 10.0.0.1/32'.
Jan 10 13:48:09.554833 osdx OSDxCLI[1768]: 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'.
Jan 10 13:48:09.649125 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'set protocols static route 0.0.0.0/0 next-hop 10.0.0.2'.
Jan 10 13:48:09.706613 osdx OSDxCLI[1768]: 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'.
Jan 10 13:48:09.814702 osdx OSDxCLI[1768]: User 'admin' added a new cfg line: 'show working'.
Jan 10 13:48:09.887071 osdx INFO[97438]: FRR daemons did not change
Jan 10 13:48:09.906354 osdx kernel: 8021q: adding VLAN 0 to HW filter on device eth0
Jan 10 13:48:09.929151 osdx (udev-worker)[97490]: Network interface NamePolicy= disabled on kernel command line.
Jan 10 13:48:10.042844 osdx systemd[1]: Started dhcpd@main.service - "DHCP Server Service instance main".
Jan 10 13:48:10.044242 osdx cfgd[1231]: [1768]Completed change to active configuration
Jan 10 13:48:10.045880 osdx dhcpd[97511]: Wrote 0 leases to leases file.
Jan 10 13:48:10.070691 osdx dhcpd[97511]:
Jan 10 13:48:10.070698 osdx dhcpd[97511]: No subnet declaration for eth0 (no IPv4 addresses).
Jan 10 13:48:10.070700 osdx dhcpd[97511]: ** Ignoring requests on eth0.  If this is not what
Jan 10 13:48:10.070703 osdx dhcpd[97511]:    you want, please write a subnet declaration
Jan 10 13:48:10.070705 osdx dhcpd[97511]:    in your dhcpd.conf file for the network segment
Jan 10 13:48:10.070707 osdx dhcpd[97511]:    to which interface eth0 is attached. **
Jan 10 13:48:10.070709 osdx dhcpd[97511]:
Jan 10 13:48:10.075312 osdx OSDxCLI[1768]: User 'admin' committed the configuration.
Jan 10 13:48:10.086424 osdx dhcpd[97511]: Server starting service.
Jan 10 13:48:10.090672 osdx OSDxCLI[1768]: User 'admin' left the configuration menu.
Jan 10 13:48:10.697386 osdx dhcpd[97511]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 20.0.0.2
Jan 10 13:48:10.833195 osdx dhcpd[97511]: DHCPDISCOVER from de:ad:be:ef:6c:20 via 30.0.0.2
Jan 10 13:48:11.697481 osdx dhcpd[97511]: DHCPOFFER on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jan 10 13:48:11.698032 osdx dhcpd[97511]: DHCPREQUEST for 20.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jan 10 13:48:11.717869 osdx dhcpd[97511]: DHCPACK on 20.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 20.0.0.2
Jan 10 13:48:11.833406 osdx dhcpd[97511]: DHCPOFFER on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Jan 10 13:48:11.833885 osdx dhcpd[97511]: DHCPREQUEST for 30.0.0.50 (10.0.0.1) from de:ad:be:ef:6c:20 (osdx) via 30.0.0.2
Jan 10 13:48:11.855070 osdx dhcpd[97511]: DHCPACK on 30.0.0.50 to de:ad:be:ef:6c:20 (osdx) via 30.0.0.2