Grid12c
RAC 12c
Hi,
I am reviewing Difference between SCAN and VIP in RAC ??
what is the difference between scan IP and VIP?
"The main purpose of SCAN is to provide ease of management/connection. For instance you can add new nodes to the cluster without changing your client TNSnames. This is because Oracle will automatically distribute requests accordingly based on the SCAN IPs which point to the underlying VIPs."
> Normally, how many scan IPs can I configure in DNS?
> How many nodes can I have in a cluster? How will the distribution be performed? Is it 1 SCANIP:1VIP? If I have 3 SCAN IPs with their 3 SCAN listeners, and more than 3 nodes, how will the distribution take place?
>SCANs uses IP not assigned to any interface. How about VIPs?
>On first node, when I do srvctl config scan results are displayed(scan IPs), but on second node nothing is displayed.
ora12c_2>srvctl config scan
SCAN name: cbs-scan.telecom.mu, Network: 1
Subnet IPv4: 10.210.228.0/255.255.255.240/bond0, static
Subnet IPv6:
SCAN 0 IPv4 VIP: 10.210.228.12
SCAN VIP is enabled.
SCAN VIP is individually enabled on nodes:
SCAN VIP is individually disabled on nodes:
SCAN 1 IPv4 VIP: 10.210.228.13
SCAN VIP is enabled.
SCAN VIP is individually enabled on nodes:
SCAN VIP is individually disabled on nodes:
SCAN 2 IPv4 VIP: 10.210.228.11
SCAN VIP is enabled.
SCAN VIP is individually enabled on nodes:
SCAN VIP is individually disabled on nodes:
>As shown above, SCAN has been deployed in cluster Network 1. But in the link above, "SCANs uses IP's not assigned to any interface." How is it possible?
Each of the SCAN IPs shown above will have their own resource and scan listener?
when I do srvctl config scan_listener
Grid12c>srvctl config scan_listener
SCAN Listener LISTENER_SCAN1 exists. Port: TCP:1521
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:
SCAN Listener LISTENER_SCAN2 exists. Port: TCP:1521
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:
SCAN Listener LISTENER_SCAN3 exists. Port: TCP:1521
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:
"Scan listeners do the bridge between clients and the underlying local listeners which are VIP-dependent."
How is the "bridge between clients and the underlying local listeners which are VIP-dependent." done?
Regards,
Joe.