Microsoft Clustering:
It is used for high availability for critical applications.
There are two types of Microsoft Clustering.
(a)
Failover Clustering
(b)
Network Load Balancer
Failover Clustering:
Windows server failover clustering (WSFC)
is a feature of the Windows server platform for improving the high availability
of applications and services.
Failover Clustering types:
Active-Active & Active- Passive
There are two types of applications also.
Cluster aware applications, examples- SQL,
Java, .Net, Exchange etc.
Cluster unaware applications, examples-
IIS, VPN, Proxy etc.
Two Node Microsoft clustering requirements
(Windows Server 2003):-
1.
Two servers with same Hardware configuration
along with same Operating system.
2.
2 NIC’s in each Nodes (1st- Prod and
2nd – Heartbeat)
3.
5 IP addresses: 2 for LAN (Prod IP- 10.10.10.5
& 10.10.10.6), 2 for Heartbeat (Local IP- 20.20.20.1 & 20.20.20.2) and
1 for Clustering (Public IP- 10.10.10.100)
4.
Both Node should be part of Domain. (Member
Servers)
5.
Two Domain users (A- For cluster configuration
and B- for run cluster service) and B password will set to never expire. Both
user should have local admin rights on both Nodes. (Node 1 and Node 2)
6.
We have to create a Host A record in the name of
Cluster in DNS line SQLcluster and IP should be public. (Example- 10.10.10.100)
7.
We have to create a Computer account in Active
Directory Users and Computers with name of Cluster (SQLcluster) and give full
permission to both Domain users (A and B) then disable this computer account.
8.
We have to create a 1GB disk for Quorum (Circle
Box in below picture) to save cluster configuration and this disk will appear
on both Nodes but only Active node will access this drive.
Start the configuration (Below mentioned):
Domain Controller & DNS server
(10.10.10.1), Host A (SQLcluster) in DNS -10.10.10.100
 |
|||
 |
|||
Switch
|
|
|
|
|
|
Node1
Node 2
Note: Microsoft cluster configuration is similar for both
Server 2003 and Server 2008 however there are few points which is essential to
know before start the configuration:
Ø
We need to download and install iScsi initiator
in Windows server 2003 server but in 2008 it is inbuilt, we just need to enable
it.
Ø
Two user account required in Windows 2003 server
for cluster configuration and start the cluster service but in 2008 server only
one user account required.
Windows 2008 cluster configuration same as 2003 (1 user [local
account] for cluster configuration and start the service): {2-Node Microsoft
Cluster}
Login on both Node (Node 1 and Node 2) from user (A- To
configure cluster and start the service).
Open Server Manager- Features- Add features- Failover clustering-
Next- Install on both Node 1 and Node 2.
Start- Programs- Administrative Tools- Failover clustering
Manager- Validate configuration-Next- Browse – Node 1 & Node 2- Add
(It will test the configuration which includes following
tasks:
Inventory tasks, Network test, Storage test and system
configuration test.
It will generate a report for all these test in HTML
format.)
-
Run all the tasks (Recommended)- Next-next- View
detais report- Next
Click on create a cluster
On Node 1
Failover cluster- Create- Add user cluster-
Next
On Node 1
Add Node- Next- Next- browse- Advanced-find
now -Next-Add- Next
Go to on Node 2 and check failover
clustering.
Difference between 2K3 and 2K8 clustering:
1.
Windows 2003 cluster service run by Domain user
account but in 2K8 by local account.
2.
Windows 2K3 sends information to Heartbeat
partner locally after every 1.2 seconds but in Windows server 2K8 it sends
after every 1 seconds.
3.
Communication will fail if Windows 2K3 server
won’t receive response from partner in 6 seconds however in 2K8 it changed to 5
seconds.
4.
Quorum disk used for storage in 2K3 but same is
known as Witness disk in 2K8.
5.
In windows 2K3 cluster configuration file report
is .log format but in 2K8 it is .HTML format.
6.
In windows 2K3 Quorum is a single point of
failure but in 2K8 Quorum woks on majority system.
7.
Windows 2K3 works on single VLAN but Windows 2K8
works on multiple VLAN.
8.
Windows 2K3 supports 8-Node Microsoft cluster
but 2K8 supports 16-Node Microsoft cluster.
Quorum Majority system in Windows 2K8:
(A)
Node majority
(B)
Node and Disk majority
(C)
Node and File share majority
(D)
No majority. Disk only
Quorum configuration
choices
You can choose from
among four possible quorum configurations:
- Node Majority (recommended for clusters with an odd number of nodes)Can sustain failures of half the nodes (rounding up) minus one. For example, a seven node cluster can sustain three node failures.
- Node and Disk Majority (recommended for clusters with an even number of nodes)Can sustain failures of half the nodes (rounding up) if the disk witness remains online. For example, a six node cluster in which the disk witness is online could sustain three node failures.Can sustain failures of half the nodes (rounding up) minus one if the disk witness goes offline or fails. For example, a six node cluster with a failed disk witness could sustain two (3-1=2) node failures.
- Node and File Share Majority (for clusters with special configurations)Works in a similar way to Node and Disk Majority, but instead of a disk witness, this cluster uses a file share witness.Note that if you use Node and File Share Majority, at least one of the available cluster nodes must contain a current copy of the cluster configuration before you can start the cluster. Otherwise, you must force the starting of the cluster through a particular node.
- No Majority: Disk Only (not recommended)Can sustain failures of all nodes except one (if the disk is online). However, this configuration is not recommended because the disk might be a single point of failure.
Visit
Microsoft Tech Net website for more information:
