Volume Replication with Failover over LAN - Virtual IP Adress in different Subnet (?)
Hello,
I'm about to configure a synchronous Volume Replication with Failover over Lan and I'm having trouble understanding the part with the virtual IP-Adress. Maybe you guys can help me out understanding it.
The How-To says that I have to configure a bonding interface on each storage-system in the same subnet. That I understand. But then it says when you have to configure the actual failover that the virtual ip-adress has to be in a different subnet. Since all my clients are going to connect to that adress via ISCSI those clients have to be in the same subnet as the virtual ip and therefore connected on the same switch. Is it even possible to have different subnets on the same switch or do I have to configure VLANs for this to work?
At first I thought the physical adresses on the bonding interfaces are just dummy-ips. But the How-To shows that the Ping-Node is in the same subnet, as the bonding interfaces. So they can't be dummy ips.
We distinguish between the networkcard-IP which is in a different subnet than the bonding-IP and also different from the virtual-IP.
The storages are synchronized over one bonding network and administrated over the other bondig network.
In theory the "clients" access over the virtual-IP but could also be done over the bonding-IP.
Our storages are connected over 2 different switches (or set of switches)
One for administration and one as SAN.
Here is an example configuration.
Storage One
eth0 IP 172.16.100.1 / mask 255.255.255.252
eth2 IP 172.16.102.1 / mask 255.255.255.252
bondig IP 10.100.111.101 / mask 255.255.255.0
eth1 IP 172.16.101.1 / mask 255.255.255.252
eth3 IP 172.16.103.1 / mask 255.255.255.252
bonding IP 10.101.1.1 / mask 255.255.255.252
Storage Two
eth0 IP 172.16.110.1 / mask 255.255.255.252
eth2 IP 172.16.112.1 / mask 255.255.255.252
bondig IP 10.110.111.101 / mask 255.255.255.0
eth1 IP 172.16.111.1 / mask 255.255.255.252
eth3 IP 172.16.113.1 / mask 255.255.255.252
bonding IP 10.101.1.2 / mask 255.255.255.252
Virtual IP is 10.101.0.101 / mask 255.255.255.0
So there is not just only separate subnetworks but different networks.
The first bonding pair is for administration and ping device etc.
The second bonding is for client access.
It could all run on the same switch but we have our iSCSI-SAN separated.