Store Half Byte-Reverse Indexed

There is a very interesting (and technical) blog about POWER systems. It is focused on low level programming and kernel internals. The name couldn’t be better: “Store Half Byte-Reverse Indexed”.

https://sthbrx.github.io/

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Alpine supports on Power

alpine2bbanner
I am pleased to announce the Alpine Linux distribution has added support for Power systems with the recent release of Alpine 3.6.

Alpine uses different approaches[1] than traditional Linux distros, thus, they were able to build a very small footprint Linux image. Version 3.6 minirootfs for Power contains less than 2Mb[2]. This small footprint capability makes it heavily favored in the containers realm[3].

Please check the Release Notes for the 3.6 release:

https://www.alpinelinux.org/posts/Alpine-3.6.0-released.html

For technical questions, please check the Community page[4].

[1]
https://wiki.alpinelinux.org/wiki/Comparison_with_other_distros
[2]
http://rsync.alpinelinux.org/alpine/v3.6/releases/ppc64le/alpine-minirootfs-3.6.0-ppc64le.tar.gz
[3]
https://store.docker.com/images/alpine
[4]
https://alpinelinux.org/community/

Boot and stop at petitboot

Depending on how you configured your POWER8 petitboot, you might want it to skip the kernel selection and boot on the default kernel.

If your default kernel is having any issue, and you want to re-select it, or, just drop at Petitboot for some other management changes, you can ask IPMI to stops at petitboot, and do not load the default kernel.

In order to do so, you should use the following ipmi command:

ipmitool -H   Host  -I lanplus  -U USER -P PASSWORD chassis bootdev bios

 

Installing NGNIX on FreeBSD/powerpc64

freebsd

As you might know, FreeBSD is also running on IBM POWER8 processor.

I just installed FreeBSD 11.0 on a VM, and installed NGINX. At this moment, FreeBSD does not have the pkg infrastructure for powerpc64, so, you need to use the ports infrastructure to install any software.

I tested it and everything I tried to build (git, zsh, vim, etc) worked fine.

This is the receipt on how to install NGINX after you install the base image:

# portsnap fetch
# portsnap update
# cd /usr/ports/www/ngninx
# make install clean

After that, NGINX will be installed on your system, and you could enable it adding the following line to /etc/rc.conf:

nginx_enable="YES"

 

Setting IPMI Power Restore Policy

If you want to set your Power machine to turn on automatically once it restarts or it is powered up, you can set the IPMI Power Restory Policy

You can choose to keep the machine off, and you need to turn it on manually. You can also choose to power the machine on automatically. The other options involves keeping the previous state, i.e, keep the machine off if it was off before, and vice-versa.

In order to do it, you should use IPMI and point to the BMC, as in the following example, where I set the machine to power on automatically when it is plugged in the power outlet.

 $ ipmitool -H  <x.x.x.x> -I lanplus -U >PASSWORD>  -P admin chassis power on

 

Possible network interface name change after upgrading kernel

Linux kernel 4.4 starts using a mechanism called Network Predictable Naming for the network interfaces. It means the name of network interfaces is based on PCI addresses of the network adapters. For example, an adapter with PCI address 0003:01:00.0 would have a mapped network interface called enP3p1s0f0.

Due to recent changes on Linux kernel to better accommodate the Network Predictable naming in ppc64el architecture, users can possibly experience change in their network interfaces’ names on Ubuntu kernel upgrade to version 4.4.0-36 or subsequent versions.

The solution to this issue is to change the network interface name on file /etc/network/interfaces to fit the new name interface got after the kernel upgrade. After this, for all subsequent kernel versions >= 4.4.0-36 there will be no more naming modifications.

Notice however that booting from old kernel after changing the interface name will present the same issue again!

This issue appears when upgrading from old kernel to 4.4.0-36 and subsequent. Happens on Ubuntu 16.04 and 14.04.5 .

Hint: to show all network interfaces on your system, just issue ls -l /sys/class/net – it’ll show all the interfaces currently available and the symbolic link to their PCI devices.

How to install IBM Java version 8 on Ubuntu

IBM provides a very powerful IBM Java for Linux. I will give the details on how to install it on Ubuntu version 16.04 (Xenial) on the ppc64el platform.

  1. Download the binary from the developerWorks page.
  2. Once you download it, give execution permission to the binary, as:chmod.png
  3. Choose the language you wish, and then the license will be shown to you, as: license.png
  4. Read the license, and if you agree, press 1.
  5. You will be able to select in which directory IBM Java will be installed, as:license.png
    1. In this case, I just pressed <Enter> to use the default path.
  6. Once you press <Enter>, the process starts. Once the process finish, you press <Enter> to exit the installer, as showed:almost
  7. After that you can load IBM Java from /opt/ibm/java-ppc64el-80/bin/java.

You can have both OpenJDK and IBM Java installed on you system, if you want to have both, as showed:

both.png

I tested these steps on both Ubuntu 15.04 and 16.04.

Try Ubuntu on POWER8 for FREE for 30 days

Canonical is collaborating with SoftLayer to offer a 30-day free trial to use the Ubuntu that you love on POWER8! This promotion, open to new and existing Softlayer customers, is a great way to discover the possibilities of Ubuntu on POWER8.

Certified Ubuntu images are now available on SoftLayer! Certified Ubuntu images provide first class security and quality assurance to guarantee the best possible experience on the industry’s leading clouds.

For more information, check: https://pages.ubuntu.com/POWER8-SoftLayer-offer.html?utm_source=Insights&utm_medium=Blog&utm_campaign=FY17_SoftlayerPromotion&