Tag Archives: clustering

Solaris Cluster 4.1 Part One: Initial Preparation

Introduction

This series of articles will cover the build of a two-node cluster running Solaris Cluster 4.1 on Solaris 11 x86. A few failover resource types will be introduced, and the end setup will have highly-available zones deployed to it. I’ll also install iPlanet on one of the zones, to illustrate how to incorporate an SMF service within a zone into the cluster-managed framework, after cloning it to save time in creating a second zone.

This is all being done under VMware Fusion 5.0 on Mac OS X. As VMware Fusion does not support disk sharing, I’ll also build a third Solaris 11 node for use as an iSCSI target and Quorum Server. Later in the process, I’ll remove the Quorum Server from the mix (as when I thought about it, an iSCSI LUN can be used for this purpose). I’ve still kept the Quorum Server details in the article, however, as it’s still of interest. Solaris 11 has totally changed the way iSCSI sharing happens, too. You have to configure COMSTAR - gone is zfs set shareiscsi=on :/

To start with, I installed Solaris 11/11 onto three VMs, clusternode1 and clusternode2 (each with 1.5GB RAM), and storagenode (with 1GB RAM). Both cluster nodes have a single 20GB disk for use as rpool, and the storagenode has a 20GB disk for rpool, and two additional 10GB disks for use as iSCSI LUNs on ZFS volumes. These LUNs will be presented to our cluster, and used for failover storage - which will then be used as the zonepaths for our highly-available zones. The node details are:

  • 10.1.1.70 - storageserver - iSCSI target and quorum server
  • 10.1.1.71 - ha-zone-1 - Zone to be provisioned to host iPlanet
  • 10.1.1.72 - ha-zone-2 - Zone to be provisioned to illustrate cloning
  • 10.1.1.80 - clusternode1 - Solaris Cluster 4.1 node
  • 10.1.1.90 - clusternode2 - Solaris Cluster 4.1 node

Each cluster node has four network interfaces, as follows:

  • net0 - e1000g0 - Public network
  • net1 - e1000g1 - Public network
  • net2 - e1000g2 - vmnet2 - a private host-only network (with no other hosts on it)
  • net3 - e1000g3 - vmnet4 - a private host-only network (with no other hosts on it)

net0 and net1 will be configured as an IPMP group with transitive probing. net2 and net3 will be used as private cluster interconnects. It is important that no other hosts are using the interconnect networks, otherwise the cluster installation software will detect the traffic and complain, as it could interfere with cluster communications.

Let’s start with some basic preparation …

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How to Cluster Oracle Weblogic 12c via the Command Line

In this article, I will show you how to create a two-node Weblogic 12c cluster using only the command line. Oracle Weblogic (formerly BEA Weblogic) is one of the most resilient, reliable and high-performance J2EE application servers that I’ve worked with. I’ve used it to host both custom applications, as well as commercial applications that required an enterprise-grade J2EE container to serve them.

The lab topology will be as follows:

Weblogic Server

Hostname

IP Address

Port

Cluster Name
AdminServer dolan 172.16.18.169 7001 N/A
test_managed_server_1 dolan 172.16.18.169 7002 TestCluster
test_managed_server_2 gooby 172.16.18.172 7002 TestCluster

As you can see, AdminServer only runs on a single node. Once the managed servers have been configured and started for the first time by way of the administration server, they can be restarted independently - thus the loss of the administration server does not impact the general running of the cluster. It will, however, prevent administration of that cluster (configuration, deployments, etc.) until such time as the administration server is back online. There are ways around this (bind the administration to a failover VIP provided by keepalived or similar) but for all but the most demanding usage, a single administration server will suffice.

Both dolan and gooby run CentOS 6.3 x86_64. All steps should be run on both nodes unless otherwise noted.

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Highly-Available Load Balancing of Apache Tomcat using HAProxy, stunnel and keepalived

This article will describe the process required to set up a highly-available SSL-enabled load balancer using HAProxy, stunnel and keepalived to front a pair of Apache Tomcat instances.

The configuration will start off simple, and extend and grow as more functionality is added. First, a session-aware HAProxy load balancer is configured. Next, Tomcat clustering is configured with session replication and the responsibility for maintaining session state is moved to Tomcat. Then, keepalived is added - providing a failover IP between HAProxy instances running on two nodes. The solution is then fully HA. To complete the article, SSL support will be enabled by way of adding stunnel in front of the HAProxy instances, and a few cleanup tasks performed.

Faithful dolan and gooby will be used for this in my lab environment. Each of the servers is running CentOS 6.3 x86_64 and already has a Tomcat instance installed to /usr/local/tomcat7 (running as the tomcat user).

As you can see, I’ve also reserved an IP address for our floating IP (or Virtual IP - VIP).

The end goal is to have dolan and gooby both running Tomcat as before, also running their own HAProxy and stunnel instances but also running a failover VIP provided by keepalived.

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