Chapter 4 Configuration Maximums

This chapter contains the configuration maximums for Oracle Private Cloud Appliance. The limits presented in the following tables represent tested, recommended limits, and are fully supported by Oracle.

Warning

Please also respect all other limitations with regard to the functionality divided between Oracle VM and Oracle Private Cloud Appliance. For example, refer to the section entitled Functional Networking Limitations in the Oracle Private Cloud Appliance Administrator's Guide.

At all times, respect the warnings and cautions throughout the documentation; most notably those at the beginning of these chapters in the Oracle Private Cloud Appliance Administrator's Guide:

Table 4.1 Virtual Machine Maximums

Item	Maximum	Notes
Virtual CPUs	48	Equals the maximum number of CPU threads for a single Oracle Server X8-2 CPU socket.
Virtual RAM (32-bit guest)	63GB
Virtual RAM (64-bit guest)	1000GB	The maximum is for a HVM guest. If more memory is assigned, performance could be adversely affected, and live migration is no longer possible. A PVHVM guest can use the installed amount of physical RAM minus a safe margin of 32GB for use by `dom0`. Windows guests with PV drivers are limited to 256GB virtual RAM.
Virtual NICs (paravirtualized guest)	31
Virtual NICs (hardware virtualized guest)	8
Virtual Disks (paravirtualized guest)	PVHVM: 107
Disks: virtual and other (hardware virtualized guest)	4	In the case of hardware virtualized guests, "disks" refers to virtual disks as well as IDE and SCSI hard drives, and cd-rom drives.

Note

These maximums do not account for CPUs allocated to any other domains, such as the control domain. The hypervisor can allocate subsets of the overall CPU, memory, and I/O resources of a server to any given logical domain.

Virtual Machine maximums assume a single virtual machine using all available resources.

Table 4.2 Oracle VM Server Maximums

Item	Maximum	Notes
CPUs	48	The Oracle Server X8-2 contains two 24-core CPUs with hyperthreading enabled.
RAM	1.5TB	This is the maximum installed amount of RAM in the Oracle Server X8-2.
Virtual Machines	128	Depending on VM sizing, the maximum number of VMs could be significantly lower. As described in Table 4.3, the total amount of disk space an RAM in use by virtual machines must not exceed the actual available storage space and physical memory. This restriction applies at the level of a single compute node as well as a server pool or tenant group.

Item

Maximum

Notes

CPUs

The Oracle Server X8-2 contains two 24-core CPUs with hyperthreading enabled.

RAM

1.5TB

This is the maximum installed amount of RAM in the Oracle Server X8-2.

Virtual Machines

128

Depending on VM sizing, the maximum number of VMs could be significantly lower.

As described in Table 4.3, the total amount of disk space an RAM in use by virtual machines must not exceed the actual available storage space and physical memory.

This restriction applies at the level of a single compute node as well as a server pool or tenant group.

Note

A limited amount of RAM is required by the hypervisor.

Table 4.3 Server Pool and Cluster Maximums

Item	Maximum	Notes
Oracle VM Servers in a clustered server pool	default: 25 custom: 24	In a base rack configuration, the maximum number of installed compute nodes is 25. All compute nodes may be a member of the default server pool. However, the default server pool cannot be empty, so any server pool associated with a custom tenant group can contain up to 24 compute nodes.
Clusters per Oracle Private Cloud Appliance	8	This maximum includes the default server pool.
Virtual disk space	depends on repository size	The total amount of disk space in use by virtual machines in the same server pool must be lower than the size of the storage repository presented to the server pool. If this limitation is exceeded, file systems may become disconnected from the virtual machines, and access to the virtual machines may be lost.
RAM usage	depends on compute node RAM	The total amount of RAM used by virtual machines in the same server pool must be lower than the amount of physical RAM installed in the compute nodes that belong to the server pool. If this limitation is exceeded, virtual machine performance drops to unacceptable levels, and the responsiveness of the entire system will be significantly reduced.

Table 4.4 Storage Maximums

Item	Maximum	Notes
iSCSI LUNs and paths per Compute Node	1000 LUNs 2000 paths	The limit is the total number of paths. In this regard, each identical LUN connected as a single multipath device must be considered as a separate path. Examples of supported configurations are: 1000 LUNs with 2 paths each, 500 LUNs with 4 paths each, or 250 LUNs with 8 paths each.
OCFS2 volume size	64TB
Files per OCFS2 volume	30,000
Virtual Disk size	10TB	The maximum is determined by the hardware capacity.
Virtual IDE drives per device	4

Table 4.5 Networking Maximums

Item	Maximum	Notes
NICs per Bond	2	Network bond configurations must never be modified by the customer.
Custom networks per Compute Node	external: 8 internal: 3	Oracle Private Cloud Appliance accepts a maximum of 3 internal networks and 8 external networks per tenant group or per compute node. This maximum includes the default internal network and the default external network.
VLANs per Server Pool	256	If the number of VLANs is larger than 256 the boot times of the servers are severely impacted. The maximum applies to any given tenant group or compute node.
Packet Size (MTU)	9000 bytes	The default maximum transmission unit for Ethernet bonds/ports is 9000 bytes.