[GCU or bgpcfgd]bgp prefix updating only fail for prefixes_v4 removal when GCU apply-patch

[wen587]

Description

Test based on BGP_ALLOWED_PREFIX yang #10142
bgp prefix removal only fails on prefixes_v4 when GCU apply-patch to remove.
Not sure it is a bug from bgpcfgd or GCU.

Steps to reproduce the issue:

1. Load bgp prefix config and check it takes into effect

admin@vlab-01:~/hijack$ cat add.load
{
    "BGP_ALLOWED_PREFIXES": {
        "DEPLOYMENT_ID|0": {
            "prefixes_v4": [
                "10.20.0.0/16",
                "10.30.0.0/16"
            ],
            "prefixes_v6": [
                "fc02:20::/64",
                "fc02:30::/64"
            ]
        }
    }
}

admin@vlab-01:~/hijack$ sudo config load -y add.load
Running command: /usr/local/bin/sonic-cfggen -j add.load --write-to-db

admin@vlab-01:~/hijack$ show run all | grep BGP_ALL -A11
    "BGP_ALLOWED_PREFIXES": {
        "DEPLOYMENT_ID|0": {
            "prefixes_v4": [
                "10.20.0.0/16",
                "20.20.0.0/16"
            ],
            "prefixes_v6": [
                "fc02:20::/64",
                "fc02:30::/64"
            ]
        }
    },

admin@vlab-01:~/hijack$ show run bgp | grep prefix
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 10 deny 0.0.0.0/0 le 17
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 20 permit 127.0.0.1/32
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 30 permit 10.20.0.0/16 le 32  <======
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 40 permit 20.20.0.0/16 le 32  <======
ip prefix-list PL_LoopbackV4 seq 5 permit 10.1.0.32/32
ip prefix-list LOCAL_VLAN_IPV4_PREFIX seq 5 permit 192.168.0.0/21
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 10 deny ::/0 le 59
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 20 deny ::/0 ge 65
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 30 permit fc02:20::/64 le 128 <=====
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 40 permit fc02:30::/64 le 128 <=====
ipv6 prefix-list PL_LoopbackV6 seq 5 permit fc00:1::/64

2. GCU apply patch to remove one prefix value. Process completed. But previous prefix v4 config is still there.

admin@vlab-01:~/hijack$ cat remove_2nd.json
[
 {
  "op": "remove",
  "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v6/1"
 },
 {
  "op": "remove",
  "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v4/1"
 }
]

admin@vlab-01:~/hijack$ sudo config apply-patch remove_2nd.json
Patch Applier: Patch application starting.
Patch Applier: Patch: [{"op": "remove", "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v6/1"}, {"op": "remove", "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v4/1"}]
Patch Applier: Applying 2 changes in order:
Patch Applier:   * [{"op": "remove", "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v4/1"}]
Patch Applier:   * [{"op": "remove", "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v6/1"}]
Patch Applier: Verifying patch updates are reflected on ConfigDB.
Patch Applier: Patch application completed.
Patch applied successfully.

admin@vlab-01:~/hijack$  sonic-db-cli CONFIG_DB hgetall "BGP_ALLOWED_PREFIXES|DEPLOYMENT_ID|0"
{'prefixes_v4@': '10.20.0.0/16', 'prefixes_v6@': 'fc02:20::/64'}
admin@vlab-01:~/hijack$ show run all | grep BGP_ALLOW -A8
    "BGP_ALLOWED_PREFIXES": {
        "DEPLOYMENT_ID|0": {
            "prefixes_v4": [
                "10.20.0.0/16"
            ],
            "prefixes_v6": [
                "fc02:20::/64"
            ]
        }

admin@vlab-01:~/hijack$ show run bgp | grep prefix
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 10 deny 0.0.0.0/0 le 17
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 20 permit 127.0.0.1/32
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 30 permit 10.20.0.0/16 le 32   <===== correct
ip prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V4 seq 40 permit 20.20.0.0/16 le 32   <===== WRONG
ip prefix-list PL_LoopbackV4 seq 5 permit 10.1.0.32/32
ip prefix-list LOCAL_VLAN_IPV4_PREFIX seq 5 permit 192.168.0.0/21
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 10 deny ::/0 le 59
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 20 deny ::/0 ge 65
ipv6 prefix-list PL_ALLOW_LIST_DEPLOYMENT_ID_0_COMMUNITY_empty_V6 seq 30 permit fc02:20::/64 le 128  <===== correct
ipv6 prefix-list PL_LoopbackV6 seq 5 permit fc00:1::/64

3. Syslog checking. I don't understand why only v4 fails to remove previous prefix.

Mar  3 05:55:31.211407 vlab-01 NOTICE config: Patch Applier: Applying 2 changes in order:
Mar  3 05:55:31.211574 vlab-01 NOTICE config: Patch Applier:   * [{"op": "remove", "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v4/1"}]
Mar  3 05:55:31.594294 vlab-01 DEBUG bgp#bgpcfgd: Received message : '('DEPLOYMENT_ID|0', 'SET', (('prefixes_v4', '10.20.0.0/16'), ('prefixes_v6', 'fc02:20::/64,fc02:30::/64')))'
Mar  3 05:55:31.595914 vlab-01 INFO bgp#bgpcfgd: BGPAllowListMgr::Updating 'Allow list' policy. deployment_id '0'. community: 'empty' prefix_v4 '['10.20.0.0/16']'. prefix_v6: '['fc02:20::/64', 'fc02:30::/64']'
...
Mar  3 05:55:31.863180 vlab-01 DEBUG bgp#bgpcfgd: BGPAllowListMgr::__update_policy. The peers configuration scheduled for updates
Mar  3 05:55:31.864233 vlab-01 INFO bgp#bgpcfgd: BGPAllowListMgr::Done
Mar  3 05:55:31.866064 vlab-01 DEBUG bgp#bgpcfgd: execute command '['vtysh', '-f', '/tmp/tmpkjuzoy7x']'.
Mar  3 05:55:31.946244 vlab-01 NOTICE config: Patch Applier:   * [{"op": "remove", "path": "/BGP_ALLOWED_PREFIXES/DEPLOYMENT_ID|0/prefixes_v6/1"}]
Mar  3 05:55:32.002791 vlab-01 DEBUG bgp#bgpcfgd: execute command '['vtysh', '-c', 'clear bgp peer-group PEER_V4 soft in']'.
Mar  3 05:55:32.165825 vlab-01 DEBUG bgp#bgpcfgd: execute command '['vtysh', '-c', 'clear bgp peer-group PEER_V6 soft in']'.
Mar  3 05:55:32.349959 vlab-01 DEBUG bgp#bgpcfgd: Received message : '('DEPLOYMENT_ID|0', 'SET', (('prefixes_v4', '10.20.0.0/16'), ('prefixes_v6', 'fc02:20::/64')))'
Mar  3 05:55:32.351224 vlab-01 INFO bgp#bgpcfgd: BGPAllowListMgr::Updating 'Allow list' policy. deployment_id '0'. community: 'empty' prefix_v4 '['10.20.0.0/16']'. prefix_v6: '['fc02:20::/64']'

Describe the results you received:

prefixes_v4 GCU removal complete. But previous config is still there.

Describe the results you expected:

Desired config removal should take effect.

Output of show version:

admin@vlab-01:~/hijack$ show version

SONiC Software Version: SONiC.master.59050-dirty-20211214.171137
Distribution: Debian 11.1
Kernel: 5.10.0-8-2-amd64
Build commit: 2a467f8eb
Build date: Tue Dec 14 17:18:24 UTC 2021
Built by: AzDevOps@sonic-build-workers-000ZFY

Platform: x86_64-kvm_x86_64-r0
HwSKU: Force10-S6000
ASIC: vs
ASIC Count: 1
Serial Number: N/A
Model Number: N/A
Hardware Revision: N/A
Uptime: 05:41:32 up 23 days, 20:21,  2 users,  load average: 0.28, 0.30, 0.28

Output of show techsupport:

(paste your output here or download and attach the file here )

Additional information you deem important (e.g. issue happens only occasionally):

[qiluo-msft]

Is this issue fixed by a PR?

[wen587]

Is this issue fixed by a PR?

Yes.