openstack - tripleo installed and was able to launch the instances.

Machine has two interfaces, eth2 for external(WAN 192.168.35.0/24) and eth3 for internal(LAN 10.0.20.0/24).

issue: unable to reach route interface by following command. (in this case, my route ipaddres 10.0.1.73)

* openstack network create public

* openstack subnet create --network public public --subnet-range 10.0.1.0/24 --allocation-pool start=10.0.1.40,end=10.0.1.80 --dns-nameserver 8.8.8.8 --gateway 10.0.1.1 --no-dhcp

* openstack network create public --provider-physical-network datacentre --provider-network-type vlan  --provider-segment 1 --external --share 

here is my ml2_conf.ini

********************************************************

[ml2]
type_drivers=geneve,vlan,flat
tenant_network_types=geneve
mechanism_drivers=ovn
path_mtu=0
extension_drivers=qos,port_security,dns

[ml2_type_geneve]
max_header_size=38
vni_ranges=1:65536

[ml2_type_vlan]
network_vlan_ranges=datacentre:1:1000

[ml2_type_flat]
flat_networks=datacentre

#[linux_bridge]
#physical_interface_mappings = datacentre:br-ex
#physical_interface_mappings = datacentre:ens20f2

[ovn]
ovn_nb_connection=tcp:10.0.1.158:6641
ovn_sb_connection=tcp:10.0.1.158:6642
ovsdb_connection_timeout=180
neutron_sync_mode=log
ovn_l3_mode=True
vif_type=ovs
ovn_metadata_enabled=True
enable_distributed_floating_ip=True
dns_servers=
ovn_emit_need_to_frag=False

****************************************************************

here is my controller network: (ens2042 external and ens2043 internal interfaces)

[root@overcloud-controller-0 ~]# ip a |more
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: ens20f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master ovs-system state UP group default qlen 1000
    link/ether 00:25:90:fe:0f:dc brd ff:ff:ff:ff:ff:ff
    inet6 fe80::225:90ff:fefe:fdc/64 scope link
       valid_lft forever preferred_lft forever
3: ens20f1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether 00:25:90:fe:0f:dd brd ff:ff:ff:ff:ff:ff
4: ens20f2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:25:90:fe:0f:de brd ff:ff:ff:ff:ff:ff
    inet 192.168.35.86/24 brd 192.168.35.255 scope global dynamic noprefixroute ens20f2
       valid_lft 39528sec preferred_lft 39528sec
    inet6 fe80::f2d5:4cdf:ab4f:4f14/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
5: ens20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:25:90:fe:0f:df brd ff:ff:ff:ff:ff:ff
    inet6 fe80::225:90ff:fefe:fdf/64 scope link
       valid_lft forever preferred_lft forever
6: ib0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 4092 qdisc fq_codel state DOWN group default qlen 256
    link/infiniband 80:00:02:08:fe:80:00:00:00:00:00:00:e4:1d:2d:03:00:21:eb:51 brd 00:ff:ff:ff:ff:12:40:1b:ff:ff:00:00:00:00:00:00:ff:ff:ff:ff
7: ovs-system: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether fa:8f:18:e9:44:e6 brd ff:ff:ff:ff:ff:ff
8: br-ex: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
    link/ether 00:25:90:fe:0f:dc brd ff:ff:ff:ff:ff:ff
    inet 10.0.1.179/24 brd 10.0.1.255 scope global br-ex
       valid_lft forever preferred_lft forever
    inet6 fe80::225:90ff:fefe:fdc/64 scope link
       valid_lft forever preferred_lft forever
9: vlan1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
    link/ether 42:f0:35:f5:cf:5f brd ff:ff:ff:ff:ff:ff
    inet 10.0.1.179/24 brd 10.0.1.255 scope global vlan1
       valid_lft forever preferred_lft forever
    inet 10.0.1.141/32 brd 10.0.1.255 scope global vlan1
       valid_lft forever preferred_lft forever
    inet 10.0.1.158/32 brd 10.0.1.255 scope global vlan1
       valid_lft forever preferred_lft forever
    inet6 fe80::40f0:35ff:fef5:cf5f/64 scope link
       valid_lft forever preferred_lft forever
10: br-int: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 76:36:79:8f:4f:b7 brd ff:ff:ff:ff:ff:ff
11: genev_sys_6081: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65000 qdisc noqueue master ovs-system state UNKNOWN group default qlen 1000
    link/ether 0e:59:d6:99:85:78 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::c59:d6ff:fe99:8578/64 scope link
       valid_lft forever preferred_lft forever

Note: I tried with 192.168.35.0/24/200.168.35.0/24 for the external network topology as well.

Thanks,

Vinesh

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