This chapter describes how to create virtual servers using Enterprise Manager Operations Control (EMOC) and to verify that servers of the same type do not run on the same underlying hardware.
Refer to your product-specific enterprise deployment guide to determine the number and size of vServers you must create.
A virtual server (vServer) is a virtual host created in the Oracle Exalogic Elastic Cloud. A virtual server is similar to a physical server. If you are planning to deploy on Virtual Exalogic, then you need to create a specific number of virtual servers to host the various components of the deployment.
Because a virtual server can run on any physical compute node in the Exalogic machine, for maximum availability, it is recommended that vServers hosting the same component do not run on the same physical server. This ensures continuity of service, even if the underlying compute node fails. For example, both wls_proda1 and wls_proda2 should not run on compute node 1. They should be distributed across two different compute nodes.
This section contains the following topics:
swap and tmp, update your vServer to use these new volumes.Parent topic: Preparing Exalogic for an Enterprise Deployment
This topic provides the prerequisites for virtual servers.
Before starting an Exalogic deployment, ensure that the following tasks have been performed:
Oracle provides a few out of the box templates for virtual servers. These templates have a base operating system of Oracle Linux 5 or Oracle Linux 6.
Virtual Servers come in a number of sizes, each size having an assigned number of virtual CPU's and memory. These templates are only examples and users can create their own with different operating system images and different CPUs and memory.
When you create a Virtual Server, you need to create a Virtual Server which is sufficient to your needs. If you are using this guide in conjunction with a product EDG such as the Identity and Access Management EDG then those guides will have guidelines on the sizes of Virtual Servers to use.
If you do not have this information, you can create a vServer with the same characteristics as a physical server. For example, if you are deploying Oracle HTTP server and it requires 1 CPU 4GB of memory and 10GB of disk space then you need to create a Virtual Server of the same size.
For additional information, refer to the product installation guides and associated support notes such as Oracle Fusion Middleware System and Requirements and Specifications document.
Oracle provides a number of base templates for Oracle Exalogic and are available to download from the Oracle E-delivery.
Server Templates contain the configuration of an individual vServer with its virtual disk. Templates can be of the format .tgz, .tar or other file types.
A distribution group prevents virtual servers assigned to it from running on the same physical nodes. By preventing different vServers of the same type running on the same physical server, you prevent the failure of the underlying physical server from taking out the complete system.
In a Fusion Middleware Exalogic implementation, the following distribution groups are required:
EDG_OTD: Prevents two Oracle Traffic Director Servers from running on the same physical server
EDG_PRODA: Prevents two instances of PRODA from running on the same physical server
EDG_PRODB: Prevents two instances of PRODB from running on the same physical server
EDG_LDAP: Prevents two LDAP instances from running on the same physical server.
This section contains the following topic:
To create a distribution group, perform the following steps:
Repeat for each distribution group to be created. Table 6-1 lists distribution groups and the number of elements for each.
Table 6-1 Number of Elements for Distribution Groups
| Distribution Group | Number of Elements |
|---|---|
|
EDG_LDAP |
2 |
|
EDG_OTD |
2 |
|
EDG_PRODA |
2 |
|
EDG_PRODB |
2 |
When you create a vServer, by default, it creates one default volume and allocates the space to swap and the root file system. For a more efficient controlled way to do this, create separate volumes for each vServer to mount for the swap and temp space.
To create separate volumes for each vServer:
This topic provides information on the vServer types along with memory and swap space.
Table 6-2 lists the vServer types used in this document. These vServer types can be used as a guide. Refer to the Oracle Fusion Middleware System Requirements and Specifications for the latest hardware requirements.
Table 6-2 vServer Types
| vServer Type | Memory | Swap Space | Tmp Space |
|---|---|---|---|
|
LARGE |
8GB |
16GB |
2GB |
|
EXTRA_LARGE |
16GB |
16GB |
2GB |
This topic provides the steps for creating a vServer.
This topic provides information on updating the root password, post network configuration and in setting the MTU size on Infiniband interfaces.
Now that the vServers have been created, you need to perform the following tasks to make them available for use.
This section contains the following topics:
This topic provides information on updating the root password.
ovsroot. Change this to a value appropriate for your organization.This topic provides information on updating the host file.
After configuration, your hosts file will look something like:
IP Address Host_Name
For example:
192.168.32.3 host1-stor
hosts file so that it contains both fully qualified and short names for each network, for example:192.168.10.3 host1-int.example.com host1-int 192.168.32.3 host1-stor.example.com host1-stor 192.168.10.3 host1-data.example.com host1-data 10.10.10.5 host1-ext.example.com host1-ext
Note:
External Network interface names are assumed to be in DNS.
Now that your vServer has been created, you must configure it as appropriate to your organization.
This typically includes the following steps:
When you created your vServer, you added the network IPoIB-Storage. This is the network the vServers use to communicate with the ZFS storage appliance.
In order for them to communicate properly, you must determine the appropriate IP address of the storage appliance to use.
To determine the IP address, perform the following steps:
If you create separate disk volumes for swap and tmp, update your vServer to use these new volumes.
The disk volumes are added to your virtual server as virtual volumes. They appear in the /dev directory as xvdb/c.
To determine the exact names, run the following command:
fdisk -l
Sample command output:
255 heads, 63 sectors/track, 1305 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000c520c Device Boot Start End Blocks Id System /dev/xvda1 * 1 32 256000 83 Linux Partition 1 does not end on cylinder boundary. /dev/xvda2 32 1305 10223616 8e Linux LVM Disk /dev/xvdb: 18.3 GB, 18253611008 bytes 255 heads, 63 sectors/track, 2219 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/xvdc: 2147 MB, 2147483648 bytes 255 heads, 63 sectors/track, 261 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000
As you can see from the output, /dev/xvda has a partition created on it so it is in use. This is the default disk.
Disks /dev/xvdb and /dev/xvdc do not have a partition and are therefore the attached disk volumes. You can determine which is which by the size of the volumes.
To use these volumes in the vServer, create a partition of type LVM. This enables the use of Linux LVM, and make resizing easier if required later. The procedure is the same if you are using the disk for swap or tmp.
This section contains the following topics:
/tmp, you can enable this by first creating a file system on it and then mounting it as a disk.This topic provides detailed steps to create a LVM partition.
Now that you have disk partitions, create logical volumes to use those disks.