CentOS Project is shifting to CentOS Stream

The CentOS project recently announced a shift in strategy for CentOS.

  • It will be shifting to an upstream build (testing patches and updates before inclusion in the upstream vendor).
  • Additionally, support for CentOS Linux 8 has been cut short, from May 31, 2029 to December 31, 2021.
  • CentOS 7 will continue to be supported as a downstream version of RHEL 7 till Jun 2024.

 

 

Where do we go from here? We can look at Rocky Linux. Rocky Linux aims to function as a downstream build as CentOS had done previously, building releases after they have been added by the upstream vendor, not before. Rocky Linux is led by Gregory Kurtzer, founder of the CentOS project.

 

White Paper on Mellanox seamless integration with OpenStack

Mellanox’s Ethernet solutions enable cloud data centers to achieve the highest efficiency through a high-performance, low latency cloud network with rich network offload with acceleration and automation features.
Check out the attached Whitepaper from Mellanox and see how we can help you get it there!

See Mellanox Seamlessly Integrates with OpenStack, Increasing Efficiency and Reducing Operational Costs

 

Joining RHEVM-Manage-Domain tool to join AD Domain

Do note that for Red Hat Enterprise Virtualization you must attach a directory server to the Manager using the Domain Management Tool, engine-manage-domains. This configuration sis for RHEV 3.5
Active Directory
Identity Management (IdM)
Red Hat Directory Server 9 (RHDS 9)
OpenLDAP

# rhevm-manage-domains add --domain=your_active_directory_domain --user=spmstest --provider=ad

Restart the ovirt-engine

# service ovirt-engine restart

Install Windows 7 with VirtIO Drivers on RHEV 3.4

One of the best ways to improve the performance of Microsoft Windows guest is to use paravirtualised devices and drivers for KVM in the guests. This provides close to bare performance (up to 95%). These drivers are provided by the virtio-win RPM packages in the RHEL.

1. The virtio-win packages can be found on RHEL server /usr/share/virtio-win/

# ls -l /usr/share/virtio-win/
drwxr-xr-x. 4 root root      4096 Oct 13 10:24 drivers
drwxr-xr-x. 2 root root      4096 Oct 13 10:24 guest-agent
-rw-r--r--. 1 root root   2949120 May 29  2014 virtio-win-1.7.1_amd64.vfd
-rw-r--r--. 1 root root 149004288 May 29  2014 virtio-win-1.7.1.iso
-rw-r--r--. 1 root root   2949120 May 29  2014 virtio-win-1.7.1_x86.vfd
lrwxrwxrwx. 1 root root        26 Oct 13 10:24 virtio-win_amd64.vfd -> virtio-win-1.7.1_amd64.vfd
lrwxrwxrwx. 1 root root        20 Oct 13 10:24 virtio-win.iso -> virtio-win-1.7.1.iso
lrwxrwxrwx. 1 root root        24 Oct 13 10:24 virtio-win_x86.vfd -> virtio-win-1.7.1_x86.vfd

You may want to add these images to the ISO Library, you can attach the virtio-drivers-*.vfd image to the virtual floppy drier beofre manually installing Windows

2. The rhev-tools-setup.iso image found in the usr/share/rhev-guest-tools-iso

# ls -l /usr/share/rhev-guest-tools-iso
-rw-r--r--. 1 root root    177272 Jul 29 16:30 LICENSES
-rw-r--r--. 1 root root 350181376 Jul 29 16:30 RHEV-toolsSetup_3.4_9.iso
lrwxrwxrwx. 1 root root        57 Oct 13 10:23 rhev-tools-setup.iso -> /usr/share/rhev-guest-tools-iso/RHEV-toolsSetup_3.4_9.iso
-rw-r--r--. 1 root root       924 Jul 29 16:30 SOURCES

3. Upload drivers and tools to the ISO Storage Domain

# rhevm-iso-uploader -u admin@internal list 
Please provide the REST API password for the admin@internal oVirt Engine user (CTRL+D to abort):
ISO Storage Domain Name   | Datacenter                | ISO Domain Status
dmn_ixora_iso_vol         | RH_Resource               | active
# rhevm-iso-uploader -u admin@internal --iso-domain=dmn_ixora_iso_vol upload  /usr/share/virtio-win/virtio-win-1.7.1_x86.vfd /usr/share/rhev-guest-tools-iso/rhev-tools-setup.iso
Please provide the REST API password for the admin@internal oVirt Engine user (CTRL+D to abort):

4. Create the new VM using the RHEV Manager

Remember to click the “Run Once”
Under the “Boot Option”,
– Attached the virtio-win-1.7.1_amd.vfd to the floppy
– Attached the MS Windows 7 ISO to the CD

RHEV_Windows7_OS

5. Update Ethernet Drivers, PCI Simple Communication Controller by attaching the RH
RHEV_Windows7_OS_Drivers

6. Once you have booted to Windows 7, go to Device Manager and run an update for the missing Ethernet, storage controller

Windows7_DeviceManager

You should see
– Red Hat VirtIO SCSI controller,
– Red Hat VirtIO SCSI pass-through controller
– Red Hat VirtIO Ethernet Adapter

Checking for Constant Time Stamp Counter

A Constant Time Stamp Counter is included in more recent Intel Processors (TSC) to reads at the processor’s maximum rate regardless of the actual CPU running rate. While this makes time keeping more consistent, but it can skew benchmarks, where a certain amount of spin-up time is spent at a lower clock rate before the OS switches the processor to the higher rate. For more information on Time Stamp Counter, do look at Time Stamp Counter (wikipedia)

To check whether your CPU support TSC, you can issue the command

# grep -q constant_tsc /proc/cpuinfo && echo "Constant TSC detected" || echo "No Constant TSC Detected"

Creation of Logical Networks on RHEV

Logical Networks allow segregation of different types of traffic. According to Red Hat Training Manual, it is recommended to have 3 types of network

  1. Management Network – Network to connect hypervisor (RHEV-H) nodes to the RHEV Manager
  2. Storage Network – Network to connect RHEV-H  to NFS and iSCSI. If you are using FC, there is no need to create a separate network since it is using SAN
  3. Public Network –  Connect the Gateway Router, the RHEV-M systems and RHEV-H Nodes

 

Configure Logical Networks

Data Centre > Networks > New Loginal Networks

NewLogicalNetwork

 

Configure Network Mac Address Pool

1. View Current Settings

# rhevm-config -g MacPoolRanges
MacPoolRanges: 00:1a:4a:9f:7e:00-00:1a:4a:9f:7e:ff version: general

2. Set the Mac range to 52:54:00:56:00:01 – 52:54:00:56:00:FF

# rhevm-config -s MacPoolRanges=52:54:00:56:00:01-52:54:00:56:00:FF

3. Restart ovirt-engine engine

# service ovirt-engine restart