Fix dhcp_relay configuration in vrf TC's

[AndriiLozovyi]

Signed-off-by: Andrii-Yosafat Lozovyi andrii-yosafatx.lozovyi@intel.com

Description of PR

Summary: Vrf test case generate and applies vrf/vrf_config_db.j2, after reboot with this generated config_db.json dhcp_relay container is down and cant get up. This leads to fail of vrf TC's on loganalyzer due to below error. It looks like config_db missed to add dhcp_server under VLAN field. With this PR dhcp_relay is getting up as expected.
Fixes # (issue)

LogAnalyzerError: expected_match: 0
               expected_missing_match: 0
               match: 2
               
               Match Messages:
               Aug  7 15:21:16.816208 ERR monit[558]: 'container_checker' status failed (3) -- Expected containers not running: dhcp_relay
               
               Aug  7 15:22:16.841585 ERR monit[558]: 'container_checker' status failed (3) -- Expected containers not running: dhcp_relay

Type of change

• Bug fix
• Testbed and Framework(new/improvement)
• Test case(new/improvement)

Back port request

• 201911
• 202012

Approach

What is the motivation for this PR?

Update vrf_config_db.j2 so that dhcp_relay could start up after config is applied.

How did you do it?

How did you verify/test it?

Run vrf/test_vrf.py, after config was applied dhcp_relay was able to start and was up.

CONTAINER ID   IMAGE                                COMMAND                  CREATED        STATUS          PORTS     NAMES
3da2544f227a   cfc3a0dd23ec                         "/usr/bin/docker_ini…"   17 hours ago   Up 3 minutes              dhcp_relay
aee89bb9b05a   docker-snmp:latest                   "/usr/local/bin/supe…"   18 hours ago   Up 34 seconds             snmp
7be979167ced   docker-sonic-telemetry:latest        "/usr/local/bin/supe…"   18 hours ago   Up 34 seconds             telemetry
b0c586a21135   docker-sonic-mgmt-framework:latest   "/usr/local/bin/supe…"   18 hours ago   Up 34 seconds             mgmt-framework
64736ff88e17   docker-lldp:latest                   "/usr/bin/docker-lld…"   18 hours ago   Up 3 minutes              lldp
9dcc1107c08b   docker-platform-monitor:latest       "/usr/bin/docker_ini…"   18 hours ago   Up 2 minutes              pmon
a900fa87a675   docker-router-advertiser:latest      "/usr/bin/docker-ini…"   18 hours ago   Up 3 minutes              radv
adc43094dbaa   docker-syncd-bfn:latest              "/usr/local/bin/supe…"   18 hours ago   Up 3 minutes              syncd
42f9e6d70253   docker-teamd:latest                  "/usr/local/bin/supe…"   18 hours ago   Up 3 minutes              teamd
d6205613327a   docker-orchagent:latest              "/usr/bin/docker-ini…"   18 hours ago   Up 3 minutes              swss
cffaa769be10   docker-fpm-frr:latest                "/usr/bin/docker_ini…"   18 hours ago   Up 3 minutes              bgp
a88d5b1e51d1   docker-database:latest               "/usr/local/bin/dock…"   18 hours ago   Up 3 minutes              database

Any platform specific information?

SONiC Software Version: SONiC.master.127871-dirty-20220728.095752
Distribution: Debian 11.4
Kernel: 5.10.0-12-2-amd64
Build commit: 746e05210
Build date: Thu Jul 28 14:13:30 UTC 2022
Built by: AzDevOps@sonic-build-workers-001UGB
Platform: x86_64-arista_7170_64c
HwSKU: Arista-7170-64C
ASIC: barefoot

Supported testbed topology if it's a new test case?

Documentation

[AndriiLozovyi]

@wangxin @yxieca could you please take a look?

[yxieca]

@kellyyeh I thought we are no longer using the vlan table for dhcp configurations?

[kellyyeh]

On master image, dhcpv6 relay is reading from DHCP_RELAY table. 202012 had discrepancy and will be fixed after this PR sonic-net/sonic-buildimage#11794

Dhcpv6 ip helper should be read from DHCP_RELAY table only

[AndriiLozovyi]

@yxieca
dhcpv6 is reading from DHCP_RELAY table, but is it expected that we should still use VLAN table to configure dhcp_servers ?
When on t0 topology dhcp_servers are deleted under VLAN table, dhcp_relay container wont start

   "VLAN": {
        "Vlan1000": {
            "vlanid": "1000"
        }
    },

$ docker ps -a
CONTAINER ID   IMAGE                                COMMAND                  CREATED       STATUS                      PORTS     NAMES
1a5ef845c0dc   36b65a6b8d5f                         "/usr/bin/docker_ini…"   2 hours ago   Exited (2) 10 minutes ago             dhcp_relay

 redis-cli -n 4 hgetall 'DHCP_RELAY|Vlan1000'
1) "dhcpv6_servers@"
2) "fc02:2000::1,fc02:2000::2,fc02:2000::3,fc02:2000::4"

Default config_db.json file after deploy of t0 topo:

 "VLAN": {
       "Vlan1000": {
           "dhcp_servers": [
               "192.0.0.1",
               "192.0.0.2",
               "192.0.0.3",
               "192.0.0.4"
           ],
           "dhcpv6_servers": [
               "fc02:2000::1",
               "fc02:2000::2",
               "fc02:2000::3",
               "fc02:2000::4"
           ],
           "vlanid": "1000"
       }

[kellyyeh]

@AndriiLozovyi sonic-net/sonic-buildimage#11794 This PR fixes dhcp relay docker to read from DHCP_RELAY table instead of VLAN table