New Features and Changes

System Requirements

You can install Oracle Linux 7 on x86-64 systems with up to 2048 logical CPUs and 64 TB of memory. The theoretical upper limit is 5120 logical CPUs and 64 TB of memory, but Oracle has not tested this configuration. A minimum of 2 logical CPUs and 1 GB of memory per logical CPU is recommended. Although the minimum disk space required for installation is 1GB, a minimum of 5 GB is recommended.

File System, Storage, and Address Space Limitations

The following table lists the maximum file size and maximum file system size for the btrfs, ext4, and XFS file systems.

File System Type	Maximum File Size	Maximum File System Size
btrfs	50 TB	50 TB
ext4	50 TB	50 TB
XFS	16 TB	500 TB

The maximum supported size for a bootable LUN is 50 TB. GPT and UEFI support are required for LUNs larger than 2 TB.

The maximum size of the address space that is available to each process is 128 TB.

Shipped Kernels

Oracle Linux 7 Update 2 includes the following kernels:

kernel-3.10.0-327.el7: Red Hat Compatible Kernel (RHCK).
kernel-uek-3.8.13-98.7.1.el7uek: Unbreakable Enterprise Kernel Release 3 (UEK R3), which is the default kernel.

makedumpfile Support for Large Memory Images

makedumpfile can now use sadump format for dumps of more than 16 TB of physical memory.

Kdump Configuration During Installation

It is now possible to configure Kdump during non-graphical installation. For limitations on using the crashkernel=auto setting, see Crash Kernel auto Setting.

Load Balancing and High Availability

Oracle Linux 7 includes the Keepalived and HAProxy technologies for balancing access to network services while maintaining continuous access to those services.

Keepalived uses the IP Virtual Server (IPVS) kernel module to provide transport layer (Layer 4) load balancing, redirecting requests for network-based services to individual members of a server cluster. IPVS monitors the status of each server and uses the Virtual Router Redundancy Protocol (VRRP) to implement high availability.

HAProxy is an application layer (Layer 7) load balancing and high availability solution that you can use to implement a reverse proxy for HTTP and TCP-based Internet services.

For more information, see Oracle Linux 7: Administrator's Guide

MySQL Community and MariaDB Packages

In the initial release of Oracle Linux 7, the MySQL Community 5.6 packages were provided on the Oracle Linux 7 full installation DVD image but were not installable using the Anaconda installer or kickstart. The ISO image for this update to Oracle Linux 7 provides support for installing either MySQL 5.6 or MariaDB by using either the Anaconda installer or kickstart.

It is not possible to install MySQL and MariaDB on the same system as package conflicts exist. Installing the MySQL packages replaces any conflicting MariaDB packages.

By default, neither MySQL 5.6 packages nor MariaDB packages are installed. It is possible to install either the MySQL 5.6 package group or the MariaDB package group on a system by using the graphical installer or kickstart, but not both package groups.

To install the MySQL 5.6 packages using kickstart, specify the @mysql package group in the %packages section. If you also specify @mariadb, it is ignored.

To install the MariaDB packages using kickstart, specify @mariadb but not @mysql in the %packages section.

Note:

If you want to install MariaDB, you must deselect the MySQL repository. Otherwise, MySQL is installed even if you select only the MariaDB group. (Bug ID 22238684)

The MySQL Community 5.7, MySQL Community 5.6 and MySQL Community 5.5 packages are also available on the Unbreakable Linux Network (ULN) and Oracle Linux yum server.

(Bug ID 20069488)

Spacewalk Client Registration

It is not necessary to install the Spacewalk client before registering an Oracle Linux 7 Update 2 system with a Spacewalk server. Instead, you can use the rhnreg_ks command, specifying the CA certificate file for the server, the server URL, and the activation key to be associated with the system.

To register a system as a client of a Spacewalk server:

Download the CA certificate file RHN-ORG-TRUSTED-SSL-CERT to the system.

In a browser tab, navigate to http://swksvr_FQDN/pub, where swksvr_FQDN is the fully qualified domain name of the Spacewalk server, and download the CA certificate file RHN-ORG-TRUSTED-SSL-CERT to /usr/share/rhn/.

Alternatively, you can use wget from the command line, for example:
```
wget -q -O /usr/share/rhn/RHN-ORG-TRUSTED-SSL-CERT http://swksvr_FQDN/pub/RHN-ORG-TRUSTED-SSL-CERT
```
Register the system with Spacewalk using the rhnreg_ks command, using the --sslCACert option to specify the certificate.
```
sudo rhnreg_ks --sslCACert=/usr/share/rhn/RHN-ORG-TRUSTED-SSL-CERT --serverUrl=https://swksvr_FQDN/XMLRPC --activationkey=activation_key
```
Specify the Spacewalk server or proxy by its fully qualified domain name.

If you need to re-register a Spacewalk client with a Spacewalk server, additionally specify the --force option.

Oracle recommends installing the Spacewalk client software after registration to support all of the features provided by Spacewalk, which include provisioning and auditing.

To install the Spacewalk client software after registration, subscribe the server to a Spacewalk Client 2.2 software channel and use yum to install the packages:

sudo yum install rhn-client-tools rhn-check rhn-setup rhnsd m2crypto yum-rhn-plugin

(Bug ID 20656368)

Technology Preview

The following features are still under development, but are made available for testing and evaluation purposes with UEK R3:

Ceph

Ceph presents a uniform view of object and block storage from a cluster of multiple physical and logical commodity-hardware storage devices. Ceph can provide fault tolerance and enhance I/O performance by replicating and striping data across the storage devices in a Storage Cluster. Ceph's monitoring and self-repair features minimize administration overhead. You can configure a Storage Cluster on non-identical hardware from different manufacturers.

Ceph for Oracle Linux is based on the Ceph Community Firefly release (v0.80). It includes the Object Store, Block Device, Storage Cluster, and Object Gateway components of Ceph. The Ceph file system (CephFS) component is also included but it is neither a technical preview feature nor is it supported.

For more information, see Oracle Linux 7 documentation.
DRBD (Distributed Replicated Block Device)

A shared-nothing, synchronously replicated block device (RAID1 over network), designed to serve as a building block for high availability (HA) clusters. It requires a cluster manager (for example, pacemaker) for automatic failover.
SCAP Workbench and the OSCAP Anaconda add-on

The OpenSCAP add-on to the Installer allows you to select a Security Content Automation Protocol (SCAP) policy by using either the graphical interface or a Kickstart %addon org_fedora_oscap section. At the end of the installation process, the compliance scanning utility (oscap) scans the system and saves the results to /root/openscap_data. The installation supports a number of standard security profiles that are provided by the openscap-scanner package. Alternatively, you can choose to use profiles from an accessible FTP or web server. Unless you specify the OpenSCAP add-on, the Installer neither applies a security policy nor performs any compliance scan during the installation process.
Transcendent memory

Transcendent Memory (tmem) provides a new approach for improving the utilization of physical memory in a virtualized environment by claiming underutilized memory in a system and making it available where it is most needed. From the perspective of an operating system, tmem is fast pseudo-RAM of indeterminate and varying size that is useful primarily when real RAM is in short supply. To learn more about this technology and its use cases, see the Transcendent Memory project page at https://oss.oracle.com/projects/tmem/.
UEFI Secure Boot

This update allows you to install and use Oracle Linux 7 on systems that have enabled UEFI Secure Boot. A system in Secure Boot mode will load only boot loaders and kernels that have been signed by Oracle.

For the RHCK, the following features are currently under technology preview:

Active Directory and LDAP sudo providers.
Block and object storage layouts for parallel NFS (pNFS).
Block device caching by LVM, which allows small, fast devices to act as caches for large, slow devices.
btrfs file system. Oracle supports btrfs with UEK R3.
Crash kernel can be configured to boot with more than a single CPU.
DIF/DIX for data integrity checking on SCSI devices other than certain, specified native HBA and storage hardware. Oracle supports DIF/DIX with UEK R3.
LSI Syncro CS feature in the megaraid_sas driver to support High-Availability Direct-Attached storage (HA-DAS) adapters.
LVM API.
More than 32 PCI slots can be configured with PCI Bridge in QEMU.
OpenLMI Software Provider.
PCI Express Bus, AHCI Bus, and USB 3.0 host adapter emulation are provided for KVM guests.
Single-Root I/O virtualization (SR-IOV) in the qlcnic driver.
Storage array management, which includes a command-line interface and the libStorageMgmt API.
The dm-era device-mapper target records changes made to blocks over a specified time period.
Trusted Network Connect.
virtio-blk-data-plane in Quick EMUlator (QEMU) improves block I/O performance.

Note:

The upstream Kpatch RPM has been removed from Oracle Linux. Customers who wish to patch their running kernel with zero downtime should evaluate Oracle's Ksplice technology, which is included at no additional cost with Oracle Linux Premier support.

Compatibility

Oracle Linux maintains user-space compatibility with Red Hat Enterprise Linux, which is independent of the kernel version that underlies the operating system. Existing applications in user space will continue to run unmodified on the Unbreakable Enterprise Kernel Release 3 (UEK R3) and no re-certifications are needed for RHEL certified applications.

To minimize impact on interoperability during releases, the Oracle Linux team works closely with third-party vendors whose hardware and software have dependencies on kernel modules. The kernel ABI for UEK R3 will remain unchanged in all subsequent updates to the initial release. UEK R3 contains changes to the kernel ABI relative to UEK R2 that require recompilation of third-party kernel modules on the system. Before installing UEK R3, verify its support status with your application vendor.

Unsupported Emulex Devices

The following Emulex LightPulse HBA devices are being desupported by Emulex and are not supported for use with Oracle Linux 7:

LP10000 (VID:10DF, DID:FA00)
LP10000S (VID:10DF, DID:FC00)
LP101 (VID:10DF, DID:F0A1)
LP1050 (VID:10DF, DID:F0A5)
LP11000S (VID:10DF, DID:FC10)
LP11000-S (VID:10DF, DID:FD11)
LP111 (VID:10DF, DID:F0D1)
LP6000 (VID:10DF, DID:1AE5)
LP7000 (VID:10DF, DID:F700)
LP8000 (VID:10DF, DID:F800)
LP9002 (VID:10DF, DID:F900)
LP952 (VID:10DF, DID:F095)
LP9802 (VID:10DF, DID:F980)
LP982 (VID:10DF, DID:F098)
LPe1000 (VID:10DF, DID:F0F5)
LPe1000-SP (VID:10DF, DID:F0F5)
LPe1002-SP (VID:10DF, DID:F0F7)
LPe11000S (VID:10DF, DID:FC20)
LPx1000 (VID:10DF, DID:FB00)