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Neutron with no available floating ip pool, can ping router gateway but not ex-net gateway

Hi guys,

I got myself in a quite complicated situation. I deployed OpenStack on OVH dedicated servers. Only 2 servers in OVH CIDR range belongs to us. So we have 2 IP in OVH network, and others IP are controlled to other users. So in this case, we don't have available floating ip pool. The OVH network has default gateway: A.B.C.254

I don't need assigning floating IP to VMs yet, I just want to VMs can ping to Internet. I added eth0 to br-ex, create a router, a tenant network, a external network.

While I set external gateway of router to external network, it automatically create a floating IP A.B.C.100 as gateway. Inside VM, I can ping to that IP, but ping to other nodes in the same CIDR will result "Unreachable".

Obviously, the A.B.C.100 is overlap with other IP in OVH network. I don't know how to solve this problem. Is it possible to setup neutron with no available floating IP pool. Can I use my network node IP as router external gateway?

Neutron with no available floating ip pool, can ping router gateway but not ex-net gateway

Hi guys,

I got myself in a quite complicated situation. I deployed OpenStack on OVH dedicated servers. Only 2 servers in OVH CIDR range belongs to us. So we have 2 IP in OVH network, us, one is compute node, and others IP are controlled one is network/controller node. Others IPs belong to other OVH users. So in this case, we don't have available floating ip pool. pool. The physical OVH network has default gateway: A.B.C.254

I don't need assigning floating IP to VMs yet, I just want to VMs can ping to Internet. I added eth0 to br-ex, create a router, a tenant network, a external network.

While I set external gateway of router to external network, it automatically create a floating IP A.B.C.100 A.B.C.100 as router gateway. Inside VM, I can ping to that IP, but ping to other nodes in the same CIDR OVH network will result "Unreachable". I can't even ping to default gateway A.B.C.254.

Obviously, the A.B.C.100 is overlap with other IP in OVH network. I don't know how to solve this problem. Is it possible to setup neutron with no available floating IP pool. Can I use my network node IP as router external gateway?

Neutron with no available floating ip pool, can ping router gateway but not ex-net gateway

Hi guys,

I got myself in a quite complicated situation. I deployed OpenStack on OVH dedicated servers. Only 2 servers in OVH CIDR range belongs to us, one is compute node, and one is network/controller node. Others IPs belong to other OVH users. So in this case, we don't have available floating ip pool. The physical OVH network has default gateway: A.B.C.254

I don't need assigning floating IP to VMs yet, I just want to VMs can ping to Internet. I added eth0 to br-ex, create a router, a tenant network, a external network.

While I set external gateway of router to external network, it automatically create a floating IP A.B.C.100 as router gateway. Inside VM, I can ping to that IP, but ping to other nodes in OVH network will result "Unreachable". I can't even ping to default gateway A.B.C.254.

Obviously, the IP: A.B.C.100 is overlap with other IP server in OVH network. I don't know how to solve this problem. Is it possible to setup neutron with no available floating IP pool. Can I use my network node IP as router external gateway?

After tcpdump, packets only reach the network node (which the A.B.C.100 tap is located), why A.B.C.100 doesn't forward packets to A.B.C.254 ?

Neutron with no available floating ip pool, can ping router gateway but not ex-net gateway

Hi guys,

I got myself in a quite complicated situation. I deployed OpenStack on OVH dedicated servers. Only 2 servers in OVH CIDR range belongs to us, one is compute node, and one is network/controller node. Others IPs belong to other OVH users. So in this case, we don't have available floating ip pool. The physical OVH network has default gateway: A.B.C.254

I don't need assigning floating IP to VMs yet, I just want to VMs can ping to Internet. I added eth0 to br-ex, create a router, a tenant network, a external network.

While I set external gateway of router to external network, it automatically create a floating IP A.B.C.100 as router gateway. Inside VM, I can ping to that IP, but ping to other nodes in OVH network will result "Unreachable". I can't even ping to default gateway A.B.C.254.

Obviously, the IP: A.B.C.100 is overlap with other server in OVH network. I don't know how to solve this problem. Is it possible to setup neutron with no available floating IP pool. Can I use my network node IP as router external gateway?

After tcpdump, packets only reach the network node (which the A.B.C.100 tap is located), why A.B.C.100 doesn't forward packets to A.B.C.254 ?

Below is ovh output:

Bridge br-ex
    Port "eth0"
        Interface "eth0"
    Port "qg-c9f1c2f1-a7"
        Interface "qg-c9f1c2f1-a7"
            type: internal
    Port br-ex
        Interface br-ex
            type: internal
Bridge br-int
    Port br-int
        Interface br-int
            type: internal
    Port "qr-ddcccc2a-61"
        tag: 1
        Interface "qr-ddcccc2a-61"
            type: internal
    Port patch-tun
        Interface patch-tun
            type: patch
            options: {peer=patch-int}
    Port "tap612a84cf-4d"
        tag: 1
        Interface "tap612a84cf-4d"
Bridge br-tun
    Port "gre-b01f694c"
        Interface "gre-b01f694c"
            type: gre
            options: {in_key=flow, local_ip="176.31.105.64", out_key=flow, remote_ip="176.31.105.76"}
    Port patch-int
        Interface patch-int
            type: patch
            options: {peer=patch-tun}
    Port br-tun
        Interface br-tun
            type: internal
    Port "gre-7f000001"
        Interface "gre-7f000001"
            type: gre
            options: {in_key=flow, local_ip="176.31.105.64", out_key=flow, remote_ip="127.0.0.1"}
ovs_version: "2.0.1"

Neutron with no available floating ip pool, can ping router gateway but not ex-net gateway

Hi guys,

I got myself in a quite complicated situation. I deployed OpenStack on OVH dedicated servers. Only 2 servers in OVH CIDR range belongs to us, one is compute node, and one is network/controller node. Others IPs belong to other OVH users. So in this case, we don't have available floating ip pool. The physical OVH network has default gateway: A.B.C.254

I don't need assigning floating IP to VMs yet, I just want to VMs can ping to Internet. Internet. I added eth0 to br-ex, create a router, a tenant network, a external network. network, and connected them together.

While I set external gateway of router to external network, it automatically create a floating IP A.B.C.100 as router gateway. gateway. Inside VM, I can ping to that IP, but ping to other nodes in OVH network will result "Unreachable". I can't even ping to default gateway A.B.C.254.

Obviously, the IP: A.B.C.100 is overlap with other server in OVH network. network. I don't know how to solve this problem. Is it possible to setup neutron with no available floating IP pool. Can I use my network node IP as router external gateway?

After checking tcpdump, I found packets only reach the network node (which the A.B.C.100 tap tap is located), why A.B.C.100 doesn't forward packets to A.B.C.254 A.B.C.254 ?

Below is ovh output:

Bridge br-ex
    Port "eth0"
        Interface "eth0"
    Port "qg-c9f1c2f1-a7"
        Interface "qg-c9f1c2f1-a7"
            type: internal
    Port br-ex
        Interface br-ex
            type: internal
Bridge br-int
    Port br-int
        Interface br-int
            type: internal
    Port "qr-ddcccc2a-61"
        tag: 1
        Interface "qr-ddcccc2a-61"
            type: internal
    Port patch-tun
        Interface patch-tun
            type: patch
            options: {peer=patch-int}
    Port "tap612a84cf-4d"
        tag: 1
        Interface "tap612a84cf-4d"
Bridge br-tun
    Port "gre-b01f694c"
        Interface "gre-b01f694c"
            type: gre
            options: {in_key=flow, local_ip="176.31.105.64", out_key=flow, remote_ip="176.31.105.76"}
    Port patch-int
        Interface patch-int
            type: patch
            options: {peer=patch-tun}
    Port br-tun
        Interface br-tun
            type: internal
    Port "gre-7f000001"
        Interface "gre-7f000001"
            type: gre
            options: {in_key=flow, local_ip="176.31.105.64", out_key=flow, remote_ip="127.0.0.1"}
ovs_version: "2.0.1"