SG cluster congiguration with 2 standby LAN

[Giuseppe_13]

I wish to configure a cluster with 2 standby lan interface:
- standby lan interface for public lan
- standby lan interface for heartbeat lan

Fo example:
lan1 = public lan
lan2 = heartbeat lan
lan3 = standby lan only for public lan
lan4 - standby lan only for hertbeat lan

How can I configure the file: CLUSTER.ascii ?

Thanks

[Matti_Kurkela · Accepted solution]

A standby interface is defined by having a NETWORK_INTERFACE line in the configuration with no corresponding HEARTBEAT_IP or STATIONARY_IP line.

When you execute cmquerycl/cmcheckconf/cmapplyconf, ServiceGuard will test connectivity between all LAN interfaces included in the configuration. It will pick each interface in each node and try to reach all other interfaces through that. With the results of this operation, ServiceGuard automatically detects what your standby interfaces are good for and selects an appropriate use for each of them.

In a basic ServiceGuard configuration, ServiceGuard uses the linkloop command (or an equivalent code) to test the interface connectivity.

At least with newer versions of ServiceGuard, cmquerycl will create comments in the CLUSTER.ascii template it produces, describing the detected network connectivity. The comments will say something like "nodeA: lanX is a possible standby interface for lanY". Use them to verify that ServiceGuard is detecting your standby interfaces correctly.

For example:
Assume a two-node cluster (nodeA and nodeB) with the network configuration as in your post.

For the network configuration to be valid:
* lan1 on nodeA must be able to access:
- lan1 on nodeB
- lan3 on nodeA
- lan3 on nodeB
* lan2 on nodeA must be able to access:
- lan2 on nodeB
- lan4 on nodeA
- lan4 on nodeB
* lan3 on nodeA must be able to access:
- lan1 on nodeA
- lan1 on nodeB
- lan3 on nodeB
* lan4 on nodeA must be able to access:
- lan2 on nodeA
- lan2 on nodeB
- lan4 on nodeB
* all these connections must work both ways, i.e. no matter which node initiates the connection.

When all this is true, ServiceGuard will automatically detect that lan3 is a valid standby interface for lan1, and lan4 is a valid standby for lan2.

The appropriate part of the CLUSTER.ascii file should look like this:

[...]
NODE_NAME nodeA

NETWORK_INTERFACE lan1
STATIONARY_IP aa.bb.cc.dd
NETWORK_INTERFACE lan2
HEARTBEAT_IP ff.gg.hh.ii
NETWORK_INTERFACE lan3
NETWORK_INTERFACE lan4

NODE_NAME nodeB

NETWORK_INTERFACE lan1
STATIONARY_IP aa.bb.cc.ee
NETWORK_INTERFACE lan2
HEARTBEAT_IP ff.gg.hh.jj
NETWORK_INTERFACE lan3
NETWORK_INTERFACE lan4

[...]

NOTE: unless there is a strict requirement that the heartbeat must not go over the public lan, I would run heartbeats over both the public LAN and the heartbeat LAN. That would make the network configuration more robust.

MK

[VK2COT]

Hello,

You already got the confirmation that two stand-by LANs are possible.

To check if the cards are properly cabled
in your case, once you set up the ServiceGuard,
run the test:

cmscancl -s

Regards,

VK2COT

[Stephen Doud]

cmquerycl will discover the networks connecting servers. It can distinquish between NICs that have IPs assigned to them and NICs that have no IP assigned but are on the same network. The latter type it designates as standby NICs. To insure a NIC is designated as a standby LAN, insure it has no IP assigned to it, but is UP per lanscan, and the NIC is connected to the network you want it to be a standby for.

If the cluster is already configured, edit the cluster configuration file and add an entry to the node section the NIC applies to, in the form:
NETWORK_INTERFACE lan2

Then perform cmapplyconf to add the new configuration to the cluster binary file.

[Steven E. Protter]

Shalom,

You can use the cluster menu option in sam and get a basic cluster.ascii file out of the deal that you can start working with.


Your plan seems sound. A standby lan needs to be on the same public corporate network as the main lan.

SEP

[Vinod Kumar Yadav]

Hi,

MCSG Cluster 2 Standby LAN Card can be configure at /etc/cmcluster/cmclconfig.ascii configuration file with NETWORK_INTERFACE & HEARTBEAT_IP or STATIONARY_IP line.

Frist Check the 4 LAN Card to be there in the server,with lanscan

0/0/1/1/0/6/0 0x001F296EBD1A 0 UP lan0 snap0 1 ETHER Yes 119
0/0/1/1/0/6/1 0x001F296EBD1B 1 UP lan1 snap1 2 ETHER Yes 119
0/0/14/1/0/4/0 0x001E0B885D28 2 UP lan2 snap2 3 ETHER Yes 119
0/0/14/1/0/4/1 0x001E0B885D29 3 UP lan3 snap3 4 ETHER Yes 119

IPs assigned to the NIC as per the lanscan.

When the Cluster Configuration frist time run the command it ServiceGuard will check the LAN Card & automatically detects what your standby LAN interfaces.

# cmquerycl -C /etc/cmcluster/cmclconfig.ascii -n node1 -n node2

After that need to check the /etc/cmcluster/cmclconfig.ascii file for LAN Card & standby LAN Card.

NODE_NAME node1

NETWORK_INTERFACE lan1
STATIONARY_IP 10.80.10.60
NETWORK_INTERFACE lan2
HEARTBEAT_IP 192.168.0.1
NETWORK_INTERFACE lan3
NETWORK_INTERFACE lan4

#Possible standby Network Interfaces for lan3: lan4

NODE_NAME node2

NETWORK_INTERFACE lan1
STATIONARY_IP 10.80.10.61
NETWORK_INTERFACE lan2
HEARTBEAT_IP 192.168.0.2
NETWORK_INTERFACE lan3
NETWORK_INTERFACE lan4

#Possible standby Network Interfaces for lan3: lan4

Thanks