[chassis] Add templates and code to support VoQ chassis iBGP peers (#5622)

This commit has following changes:

* Add templates and code to support VoQ chassis iBGP peers

* Add support to convert a new VoQChassisInternal element in the
   BGPSession element of the minigraph to a new BGP_VOQ_CHASSIS_NEIGHBOR 
   table in CONFIG_DB.
* Add a new set of "voq_chassis" templates to docker-fpm-frr
* Add a new BGP peer manager to bgpcfgd to add neighbors from the
  BGP_VOQ_CHASSIS_NEIGHBOR table using the voq_chassis templates.
* Add a test case for minigraph.py, making sure the VoQChassisInternal
  element creates a BGP_VOQ_CHASSIS_NEIGHBOR entry, but not if its
  value is "false".
* Add a set of test cases for the new voq_chassis templates in
  sonic-bgpcfgd tests.

Note that the templates expect the new
"bgp bestpath peer-type multipath-relax" bgpd configuration to be
available.

Signed-off-by: Joanne Mikkelson <jmmikkel@arista.com>

dockers/docker-fpm-frr/frr/bgpd/templates/voq_chassis/instance.conf.j2

@@ -0,0 +1,35 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor {{ neighbor_addr }} peer-group VOQ_CHASSIS_PEER
+  neighbor {{ neighbor_addr }} remote-as {{ bgp_session['asn'] }}
+  neighbor {{ neighbor_addr }} description {{ bgp_session['name'] }}
+{# set the bgp neighbor timers if they have not default values #}
+{% if     (bgp_session['keepalive'] is defined and bgp_session['keepalive'] | int != 60)
+      or  (bgp_session['holdtime'] is defined  and bgp_session['holdtime']  | int != 180) %}
+  neighbor {{ neighbor_addr }} timers {{ bgp_session['keepalive'] | default("60") }} {{ bgp_session['holdtime'] | default("180") }}
+{% endif %}
+!
+{% if 'admin_status' in bgp_session and bgp_session['admin_status'] == 'down' or 'admin_status' not in bgp_session and 'default_bgp_status' in CONFIG_DB__DEVICE_METADATA['localhost'] and CONFIG_DB__DEVICE_METADATA['localhost']['default_bgp_status'] == 'down' %}
+  neighbor {{ neighbor_addr }} shutdown
+{% endif %}
+!
+  address-family ipv4
+{% if constants.bgp.maximum_paths.enabled is defined and constants.bgp.maximum_paths.enabled %}
+    maximum-paths ibgp {{ constants.bgp.maximum_paths.ipv4 | default(64) }}
+{% endif %}
+!
+  exit-address-family
+!
+  address-family ipv6
+{% if constants.bgp.maximum_paths.enabled is defined and constants.bgp.maximum_paths.enabled %}
+    maximum-paths ibgp {{ constants.bgp.maximum_paths.ipv6 | default(64) }}
+{% endif %}
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

dockers/docker-fpm-frr/frr/bgpd/templates/voq_chassis/peer-group.conf.j2

@@ -0,0 +1,23 @@
+!
+! template: bgpd/templates/voq_chassis/peer-group.conf.j2
+!
+  neighbor VOQ_CHASSIS_PEER peer-group
+  address-family ipv4
+{% if CONFIG_DB__DEVICE_METADATA['localhost']['type'] == 'ToRRouter' %}
+    neighbor VOQ_CHASSIS_PEER allowas-in 1
+{% endif %}
+    neighbor VOQ_CHASSIS_PEER activate
+    neighbor VOQ_CHASSIS_PEER addpath-tx-all-paths
+    neighbor VOQ_CHASSIS_PEER soft-reconfiguration inbound
+  exit-address-family
+  address-family ipv6
+{% if CONFIG_DB__DEVICE_METADATA['localhost']['type'] == 'ToRRouter' %}
+    neighbor VOQ_CHASSIS_PEER allowas-in 1
+{% endif %}
+    neighbor VOQ_CHASSIS_PEER activate
+    neighbor VOQ_CHASSIS_PEER addpath-tx-all-paths
+    neighbor VOQ_CHASSIS_PEER soft-reconfiguration inbound
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/peer-group.conf.j2
+!

dockers/docker-fpm-frr/frr/bgpd/templates/voq_chassis/policies.conf.j2

@@ -0,0 +1,7 @@
+!
+! template: bgpd/templates/voq_chassis/policies.conf.j2
+!
+!
+!
+! end of template: bgpd/templates/voq_chassis/policies.conf.j2
+!

files/image_config/constants/constants.yml

@@ -54,3 +54,7 @@ constants:
         db_table: "BGP_PEER_RANGE"
         peer_group: "BGP_SPEAKER"
         template_dir: "dynamic"
+      voq_chassis: # peer_type
+        enabled: true
+        db_table: "BGP_VOQ_CHASSIS_NEIGHBOR"
+        template_dir: "voq_chassis"

src/sonic-bgpcfgd/bgpcfgd/main.py

@@ -43,6 +43,7 @@ def do_work():
         InterfaceMgr(common_objs, "CONFIG_DB", swsscommon.CFG_LOOPBACK_INTERFACE_TABLE_NAME),
         InterfaceMgr(common_objs, "CONFIG_DB", swsscommon.CFG_VLAN_INTF_TABLE_NAME),
         InterfaceMgr(common_objs, "CONFIG_DB", swsscommon.CFG_LAG_INTF_TABLE_NAME),
+        InterfaceMgr(common_objs, "CONFIG_DB", swsscommon.CFG_VOQ_INBAND_INTERFACE_TABLE_NAME),
         # State DB managers
         ZebraSetSrc(common_objs, "STATE_DB", swsscommon.STATE_INTERFACE_TABLE_NAME),
         # Peer Managers
@@ -50,6 +51,7 @@ def do_work():
         BGPPeerMgrBase(common_objs, "CONFIG_DB", swsscommon.CFG_BGP_INTERNAL_NEIGHBOR_TABLE_NAME, "internal", False),
         BGPPeerMgrBase(common_objs, "CONFIG_DB", "BGP_MONITORS", "monitors", False),
         BGPPeerMgrBase(common_objs, "CONFIG_DB", "BGP_PEER_RANGE", "dynamic", False),
+        BGPPeerMgrBase(common_objs, "CONFIG_DB", "BGP_VOQ_CHASSIS_NEIGHBOR", "voq_chassis", False),
         # AllowList Managers
         BGPAllowListMgr(common_objs, "CONFIG_DB", "BGP_ALLOWED_PREFIXES"),
         # BBR Manager

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/param_all.json

@@ -0,0 +1,22 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {}
+    },
+    "neighbor_addr": "10.10.10.10",
+    "bgp_session": {
+        "asn": "555",
+        "name": "internal1",
+        "keepalive": "5",
+        "holdtime": "30",
+        "admin_status": "down"
+    },
+    "constants": {
+        "bgp": {
+            "maximum_paths": {
+                "enabled": "true",
+                "ipv4": "32",
+                "ipv6": "24"
+            }
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/param_base.json

@@ -0,0 +1,17 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {}
+    },
+    "neighbor_addr": "10.10.10.10",
+    "bgp_session": {
+        "asn": "555",
+        "name": "internal1"
+    },
+    "constants": {
+        "bgp": {
+            "maximum_paths": {
+                "enabled": "true"
+            }
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/param_shutdown_1.json

@@ -0,0 +1,19 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {
+            "default_bgp_status": "down"
+        }
+    },
+    "neighbor_addr": "10.10.10.10",
+    "bgp_session": {
+        "asn": "555",
+        "name": "internal1"
+    },
+    "constants": {
+        "bgp": {
+            "maximum_paths": {
+                "enabled": "true"
+            }
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/param_shutdown_2.json

@@ -0,0 +1,19 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {
+            "default_bgp_status": "up"
+        }
+    },
+    "neighbor_addr": "10.10.10.10",
+    "bgp_session": {
+        "asn": "555",
+        "name": "internal1"
+    },
+    "constants": {
+        "bgp": {
+            "maximum_paths": {
+                "enabled": "true"
+            }
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/param_timers_1.json

@@ -0,0 +1,18 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {}
+    },
+    "neighbor_addr": "10.10.10.10",
+    "bgp_session": {
+        "asn": "555",
+        "name": "internal1",
+        "keepalive": "5"
+    },
+    "constants": {
+        "bgp": {
+            "maximum_paths": {
+                "enabled": "true"
+            }
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/param_timers_2.json

@@ -0,0 +1,18 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {}
+    },
+    "neighbor_addr": "10.10.10.10",
+    "bgp_session": {
+        "asn": "555",
+        "name": "internal1",
+        "holdtime": "240"
+    },
+    "constants": {
+        "bgp": {
+            "maximum_paths": {
+                "enabled": "true"
+            }
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/result_all.conf

@@ -0,0 +1,23 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor 10.10.10.10 peer-group VOQ_CHASSIS_PEER
+  neighbor 10.10.10.10 remote-as 555
+  neighbor 10.10.10.10 description internal1
+  neighbor 10.10.10.10 timers 5 30
+  neighbor 10.10.10.10 shutdown
+  address-family ipv4
+    maximum-paths ibgp 32
+!
+  exit-address-family
+!
+  address-family ipv6
+    maximum-paths ibgp 24
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/result_base.conf

@@ -0,0 +1,21 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor 10.10.10.10 peer-group VOQ_CHASSIS_PEER
+  neighbor 10.10.10.10 remote-as 555
+  neighbor 10.10.10.10 description internal1
+  address-family ipv4
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+  address-family ipv6
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/result_shutdown_1.conf

@@ -0,0 +1,22 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor 10.10.10.10 peer-group VOQ_CHASSIS_PEER
+  neighbor 10.10.10.10 remote-as 555
+  neighbor 10.10.10.10 description internal1
+  neighbor 10.10.10.10 shutdown
+  address-family ipv4
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+  address-family ipv6
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/result_shutdown_2.conf

@@ -0,0 +1,21 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor 10.10.10.10 peer-group VOQ_CHASSIS_PEER
+  neighbor 10.10.10.10 remote-as 555
+  neighbor 10.10.10.10 description internal1
+  address-family ipv4
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+  address-family ipv6
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/result_timers_1.conf

@@ -0,0 +1,22 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor 10.10.10.10 peer-group VOQ_CHASSIS_PEER
+  neighbor 10.10.10.10 remote-as 555
+  neighbor 10.10.10.10 description internal1
+  neighbor 10.10.10.10 timers 5 180
+  address-family ipv4
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+  address-family ipv6
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/instance.conf/result_timers_2.conf

@@ -0,0 +1,22 @@
+!
+! template: bgpd/templates/voq_chassis/instance.conf.j2
+!
+  bgp bestpath as-path multipath-relax
+  bgp bestpath peer-type multipath-relax
+!
+  neighbor 10.10.10.10 peer-group VOQ_CHASSIS_PEER
+  neighbor 10.10.10.10 remote-as 555
+  neighbor 10.10.10.10 description internal1
+  neighbor 10.10.10.10 timers 60 240
+  address-family ipv4
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+  address-family ipv6
+    maximum-paths ibgp 64
+!
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/instance.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/peer-group.conf/param_all.json

@@ -0,0 +1,7 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {
+            "type": "ToRRouter"
+        }
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/peer-group.conf/param_base.json

@@ -0,0 +1,5 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {}
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/peer-group.conf/result_all.conf

@@ -0,0 +1,19 @@
+!
+! template: bgpd/templates/voq_chassis/peer-group.conf.j2
+!
+  neighbor VOQ_CHASSIS_PEER peer-group
+  address-family ipv4
+    neighbor VOQ_CHASSIS_PEER allowas-in 1
+    neighbor VOQ_CHASSIS_PEER activate
+    neighbor VOQ_CHASSIS_PEER addpath-tx-all-paths
+    neighbor VOQ_CHASSIS_PEER soft-reconfiguration inbound
+  exit-address-family
+  address-family ipv6
+    neighbor VOQ_CHASSIS_PEER allowas-in 1
+    neighbor VOQ_CHASSIS_PEER activate
+    neighbor VOQ_CHASSIS_PEER addpath-tx-all-paths
+    neighbor VOQ_CHASSIS_PEER soft-reconfiguration inbound
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/peer-group.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/peer-group.conf/result_base.conf

@@ -0,0 +1,17 @@
+!
+! template: bgpd/templates/voq_chassis/peer-group.conf.j2
+!
+  neighbor VOQ_CHASSIS_PEER peer-group
+  address-family ipv4
+    neighbor VOQ_CHASSIS_PEER activate
+    neighbor VOQ_CHASSIS_PEER addpath-tx-all-paths
+    neighbor VOQ_CHASSIS_PEER soft-reconfiguration inbound
+  exit-address-family
+  address-family ipv6
+    neighbor VOQ_CHASSIS_PEER activate
+    neighbor VOQ_CHASSIS_PEER addpath-tx-all-paths
+    neighbor VOQ_CHASSIS_PEER soft-reconfiguration inbound
+  exit-address-family
+!
+! end of template: bgpd/templates/voq_chassis/peer-group.conf.j2
+!

src/sonic-bgpcfgd/tests/data/voq_chassis/policies.conf/param_base.json

@@ -0,0 +1,5 @@
+{
+    "CONFIG_DB__DEVICE_METADATA": {
+        "localhost": {}
+    }
+}

src/sonic-bgpcfgd/tests/data/voq_chassis/policies.conf/result_base.conf

@@ -0,0 +1,7 @@
+!
+! template: bgpd/templates/voq_chassis/policies.conf.j2
+!
+!
+!
+! end of template: bgpd/templates/voq_chassis/policies.conf.j2
+!

src/sonic-bgpcfgd/tests/test_templates.py

@@ -140,3 +140,15 @@ def test_monitors_pg():
 def test_monitors_instance():
     test_data = load_tests("monitors", "instance.conf")
     run_tests("monitors_instance", *test_data)
+
+def test_voq_chassis_policies():
+    test_data = load_tests("voq_chassis", "policies.conf")
+    run_tests("voq_chassis_policies", *test_data)
+
+def test_voq_chassis_pg():
+    test_data = load_tests("voq_chassis", "peer-group.conf")
+    run_tests("voq_chassis_pg", *test_data)
+
+def test_voq_chassis_instance():
+    test_data = load_tests("voq_chassis", "instance.conf")
+    run_tests("voq_chassis_instance", *test_data)

src/sonic-config-engine/minigraph.py

@@ -681,6 +681,7 @@ def parse_host_loopback(dpg, hname):
 def parse_cpg(cpg, hname, local_devices=[]):
     bgp_sessions = {}
     bgp_internal_sessions = {}
+    bgp_voq_chassis_sessions = {}
     myasn = None
     bgp_peers_with_range = {}
     for child in cpg:
@@ -702,46 +703,40 @@ def parse_cpg(cpg, hname, local_devices=[]):
                     keepalive = 60
                 nhopself = 1 if session.find(str(QName(ns, "NextHopSelf"))) is not None else 0
 
+                # choose the right table and admin_status for the peer
+                voq_chassis = session.find(str(QName(ns, "VoQChassisInternal")))
+                if voq_chassis is not None and voq_chassis.text == "true":
+                    table = bgp_voq_chassis_sessions
+                    admin_status = 'up'
+                elif end_router.lower() in local_devices and start_router.lower() in local_devices:
+                    table = bgp_internal_sessions
+                    admin_status = 'up'
+                else:
+                    table = bgp_sessions
+                    admin_status = None
+
                 if end_router.lower() == hname.lower():
-                    if end_router.lower() in local_devices and start_router.lower() in local_devices:
+                    table[start_peer.lower()] = {
-                        bgp_internal_sessions[start_peer.lower()] = {
+                        'name': start_router,
-                            'name': start_router,
+                        'local_addr': end_peer.lower(),
-                            'local_addr': end_peer.lower(),
+                        'rrclient': rrclient,
-                            'rrclient': rrclient,
+                        'holdtime': holdtime,
-                            'holdtime': holdtime,
+                        'keepalive': keepalive,
-                            'keepalive': keepalive,
+                        'nhopself': nhopself
-                            'nhopself': nhopself,
+                    }
-                            'admin_status': 'up'
+                    if admin_status:
-                        }
+                        table[start_peer.lower()]['admin_status'] = admin_status
-                    else:
-                        bgp_sessions[start_peer.lower()] = {
-                            'name': start_router,
-                            'local_addr': end_peer.lower(),
-                            'rrclient': rrclient,
-                            'holdtime': holdtime,
-                            'keepalive': keepalive,
-                            'nhopself': nhopself
-                        }
                 elif start_router.lower() == hname.lower():
-                    if end_router.lower() in local_devices and start_router.lower() in local_devices:
+                    table[end_peer.lower()] = {
-                        bgp_internal_sessions[end_peer.lower()] = {
+                        'name': end_router,
-                            'name': end_router,
+                        'local_addr': start_peer.lower(),
-                            'local_addr': start_peer.lower(),
+                        'rrclient': rrclient,
-                            'rrclient': rrclient,
+                        'holdtime': holdtime,
-                            'holdtime': holdtime,
+                        'keepalive': keepalive,
-                            'keepalive': keepalive,
+                        'nhopself': nhopself
-                            'nhopself': nhopself,
+                    }
-                            'admin_status': 'up'
+                    if admin_status:
-                        }
+                        table[end_peer.lower()]['admin_status'] = admin_status
-                    else:
-                        bgp_sessions[end_peer.lower()] = {
-                            'name': end_router,
-                            'local_addr': start_peer.lower(),
-                            'rrclient': rrclient,
-                            'holdtime': holdtime,
-                            'keepalive': keepalive,
-                            'nhopself': nhopself
-                        }
         elif child.tag == str(QName(ns, "Routers")):
             for router in child.findall(str(QName(ns1, "BGPRouterDeclaration"))):
                 asn = router.find(str(QName(ns1, "ASN"))).text
@@ -772,12 +767,19 @@ def parse_cpg(cpg, hname, local_devices=[]):
                         bgp_internal_session = bgp_internal_sessions[peer]
                         if hostname.lower() == bgp_internal_session['name'].lower():
                             bgp_internal_session['asn'] = asn
+                    for peer in bgp_voq_chassis_sessions:
+                        bgp_session = bgp_voq_chassis_sessions[peer]
+                        if hostname.lower() == bgp_session['name'].lower():
+                            bgp_session['asn'] = asn
 
     bgp_monitors = { key: bgp_sessions[key] for key in bgp_sessions if 'asn' in bgp_sessions[key] and bgp_sessions[key]['name'] == 'BGPMonitor' }
-    bgp_sessions = { key: bgp_sessions[key] for key in bgp_sessions if 'asn' in bgp_sessions[key] and int(bgp_sessions[key]['asn']) != 0 }
+    def filter_bad_asn(table):
-    bgp_internal_sessions = { key: bgp_internal_sessions[key] for key in bgp_internal_sessions if 'asn' in bgp_internal_sessions[key] and int(bgp_internal_sessions[key]['asn']) != 0 }
+        return { key: table[key] for key in table if 'asn' in table[key] and int(table[key]['asn']) != 0 }
+    bgp_sessions = filter_bad_asn(bgp_sessions)
+    bgp_internal_sessions = filter_bad_asn(bgp_internal_sessions)
+    bgp_voq_chassis_sessions = filter_bad_asn(bgp_voq_chassis_sessions)
 
-    return bgp_sessions, bgp_internal_sessions, myasn, bgp_peers_with_range, bgp_monitors
+    return bgp_sessions, bgp_internal_sessions, bgp_voq_chassis_sessions, myasn, bgp_peers_with_range, bgp_monitors
 
 
 def parse_meta(meta, hname):
@@ -1153,7 +1155,7 @@ def parse_xml(filename, platform=None, port_config_file=None, asic_name=None, hw
             if child.tag == str(QName(ns, "DpgDec")):
                 (intfs, lo_intfs, mvrf, mgmt_intf, vlans, vlan_members, pcs, pc_members, acls, vni, tunnel_intfs, dpg_ecmp_content) = parse_dpg(child, hostname)
             elif child.tag == str(QName(ns, "CpgDec")):
-                (bgp_sessions, bgp_internal_sessions, bgp_asn, bgp_peers_with_range, bgp_monitors) = parse_cpg(child, hostname)
+                (bgp_sessions, bgp_internal_sessions, bgp_voq_chassis_sessions, bgp_asn, bgp_peers_with_range, bgp_monitors) = parse_cpg(child, hostname)
             elif child.tag == str(QName(ns, "PngDec")):
                 (neighbors, devices, console_dev, console_port, mgmt_dev, mgmt_port, port_speed_png, console_ports, mux_cable_ports, is_storage_device, png_ecmp_content) = parse_png(child, hostname, dpg_ecmp_content)
             elif child.tag == str(QName(ns, "UngDec")):
@@ -1169,7 +1171,7 @@ def parse_xml(filename, platform=None, port_config_file=None, asic_name=None, hw
                 (intfs, lo_intfs, mvrf, mgmt_intf, vlans, vlan_members, pcs, pc_members, acls, vni, tunnel_intfs, dpg_ecmp_content) = parse_dpg(child, asic_name)
                 host_lo_intfs = parse_host_loopback(child, hostname)
             elif child.tag == str(QName(ns, "CpgDec")):
-                (bgp_sessions, bgp_internal_sessions, bgp_asn, bgp_peers_with_range, bgp_monitors) = parse_cpg(child, asic_name, local_devices)
+                (bgp_sessions, bgp_internal_sessions, bgp_voq_chassis_sessions, bgp_asn, bgp_peers_with_range, bgp_monitors) = parse_cpg(child, asic_name, local_devices)
             elif child.tag == str(QName(ns, "PngDec")):
                 (neighbors, devices, port_speed_png) = parse_asic_png(child, asic_name, hostname)
             elif child.tag == str(QName(ns, "MetadataDeclaration")):
@@ -1241,6 +1243,7 @@ def parse_xml(filename, platform=None, port_config_file=None, asic_name=None, hw
     results['BGP_MONITORS'] = bgp_monitors
     results['BGP_PEER_RANGE'] = bgp_peers_with_range
     results['BGP_INTERNAL_NEIGHBOR'] = bgp_internal_sessions
+    results['BGP_VOQ_CHASSIS_NEIGHBOR'] = bgp_voq_chassis_sessions
     if mgmt_routes:
         # TODO: differentiate v4 and v6
         next(iter(mgmt_intf.values()))['forced_mgmt_routes'] = mgmt_routes

src/sonic-config-engine/tests/simple-sample-graph.xml

@@ -20,6 +20,7 @@
         <Multihop>1</Multihop>
         <HoldTime>180</HoldTime>
         <KeepAliveTime>60</KeepAliveTime>
+        <VoQChassisInternal>false</VoQChassisInternal>
       </BGPSession>
       <BGPSession>
         <StartRouter>switch-t0</StartRouter>
@@ -49,6 +50,26 @@
         <HoldTime>180</HoldTime>
         <KeepAliveTime>60</KeepAliveTime>
       </BGPSession>
+      <BGPSession>
+        <StartRouter>switch-t0</StartRouter>
+        <StartPeer>FC00::75</StartPeer>
+        <EndRouter>ARISTA02T1</EndRouter>
+        <EndPeer>FC00::76</EndPeer>
+        <Multihop>1</Multihop>
+        <HoldTime>180</HoldTime>
+        <KeepAliveTime>60</KeepAliveTime>
+      </BGPSession>
+      <BGPSession>
+        <MacSec>false</MacSec>
+        <StartRouter>switch-t0</StartRouter>
+        <StartPeer>10.2.0.20</StartPeer>
+        <EndRouter>CHASSIS_PEER</EndRouter>
+        <EndPeer>10.2.0.21</EndPeer>
+        <Multihop>1</Multihop>
+        <HoldTime>180</HoldTime>
+        <KeepAliveTime>60</KeepAliveTime>
+        <VoQChassisInternal>true</VoQChassisInternal>
+      </BGPSession>
     </PeeringSessions>
     <Routers xmlns:a="http://schemas.datacontract.org/2004/07/Microsoft.Search.Autopilot.Evolution">
       <a:BGPRouterDeclaration>
@@ -82,6 +103,12 @@
             <RouteMapOut i:nil="true"/>
             <Vrf i:nil="true"/>
           </BGPPeer>
+          <BGPPeer>
+            <Address>10.2.0.21</Address>
+            <RouteMapIn i:nil="true"/>
+            <RouteMapOut i:nil="true"/>
+            <Vrf i:nil="true"/>
+          </BGPPeer>
         </a:Peers>
         <a:RouteMaps/>
       </a:BGPRouterDeclaration>
@@ -105,6 +132,11 @@
         <a:Hostname>ARISTA04T1</a:Hostname>
         <a:RouteMaps/>
       </a:BGPRouterDeclaration>
+      <a:BGPRouterDeclaration>
+        <a:ASN>65100</a:ASN>
+        <a:Hostname>CHASSIS_PEER</a:Hostname>
+        <a:RouteMaps/>
+      </a:BGPRouterDeclaration>
     </Routers>
   </CpgDec>
   <DpgDec>

src/sonic-config-engine/tests/test_cfggen.py

@@ -586,6 +586,19 @@ class TestCfgGen(TestCase):
             utils.to_dict("{'10.20.30.40': {'rrclient': 0, 'name': 'BGPMonitor', 'local_addr': '10.1.0.32', 'nhopself': 0, 'holdtime': '10', 'asn': '0', 'keepalive': '3'}}")
         )
 
+    def test_minigraph_bgp_voq_chassis_peer(self):
+        argument = '-m "' + self.sample_graph_simple + '" -p "' + self.port_config + '" -v "BGP_VOQ_CHASSIS_NEIGHBOR[\'10.2.0.21\']"'
+        output = self.run_script(argument)
+        self.assertEqual(
+            utils.to_dict(output.strip()),
+            utils.to_dict("{'rrclient': 0, 'name': 'CHASSIS_PEER', 'local_addr': '10.2.0.20', 'nhopself': 0, 'holdtime': '180', 'asn': '65100', 'keepalive': '60', 'admin_status': 'up'}")
+        )
+
+        # make sure VoQChassisInternal value of false is honored
+        argument = '-m "' + self.sample_graph_simple + '" -p "' + self.port_config + '" -v "BGP_VOQ_CHASSIS_NEIGHBOR[\'10.0.0.57\']"'
+        output = self.run_script(argument)
+        self.assertEqual(output.strip(), "")
+
     def test_minigraph_sub_port_interfaces(self, check_stderr=True):
         try:
             print('\n    Change device type to %s' % (BACKEND_TOR_ROUTER))