It’s been close to a year since I updated our cluster; I was going to do it over Christmas, but never quite got around to it. The period of social distancing (and procrastinating on my research) is a great time, right? The cluster is running Centos 7. The biggest issue with upgrading it is the Lustre file system. These are all my notes on the upgrade process. I’m hoping by writing them down here, my life will be somewhat easier the next time I need to do this. Learning how Lustre works all over again every time I do an update is an involved process!
Lustre is very picky about the version of the Linux kernel. This means we can’t just do a blanket “sudo yum update” on the system. We need to upgrade to the specific kernel version that is required by the new version of Lustre we will be installing.
On wyeast, the Lustre server is installed across three different nodes: wyeast-lustre01, wyeast-lustre02, and wyeast-lustre03. The metadata server is on the first node, and the object storage targets are stored on lustre02 and lustre03.
First, update the list of updates that yum knows about:
sudo yum makecache
Next, look at the lustre-server repo and find the current version of the Lustre server and the Linux kernel it uses.
sudo yum repo-pkgs lustre-server list
From this, I found that the current Lustre server version is 2.12.4. I checked the changelog on lustre.org to determine the kernel version needed:
http://wiki.lustre.org/Lustre_2.12.4_Changelog
The Linux kernel needed is actually available in the Lustre-server repo:
kernel-3.10.0-1062.9.1.el7_lustre
So I needed to make sure to install that particular version and not the most up-to-date kernel.
sudo yum repo-pkgs lustre-server update kernel-3.10.0-1062.9.1.el7_lustre kernel-devel-3.10.0-1062.9.1.el7_lustre kernel-headers-3.10.0-1062.9.1.el7_lustre
After that, I checked the current list of other updates available in the Lustre server repository.
sudo yum repo-pkgs lustre-server list
Next, I updated all the Lustre packages that were already installed:
sudo yum repo-pkgs lustre-server update kmod-lustre.x86_64 kmod-lustre-osd-ldiskfs.x86_64 libnvpair1.x86_64 libuutil1.x86_64 libzfs2.x86_64 libzpool2.x86_64 lustre.x86_64 lustre-osd-ldiskfs-mount.x86_64 lustre-osd-zfs-mount.x86_64 lustre-resource-agents.x86_64 lustre-zfs-dkms.noarch spl.x86_64 spl-dkms.noarch zfs.x86_64 zfs-dkms.noarch
Finally, I’ll update all the other system software, carefully excluding the Linux kernel packages:
sudo yum -x kernel,kernel-headers,kernel-debug-devel,kernel-tools,kernel-tools-libs,kmod-lustre.x86_64,kmod-lustre-osd-ldiskfs.x86_64,libnvpair1.x86_64,libuutil1.x86_64,libzfs2.x86_64,libzpool2.x86_64,lustre.x86_64,lustre-osd-ldiskfs-mount.x86_64,lustre-osd-zfs-mount.x86_64,lustre-resource-agents.x86_64,lustre-zfs-dkms.noarch,spl.x86_64,spl-dkms.noarch,spl-dkms.noarch,zfs.x86_64,zfs-dkms.noarch,kernel-devel update
That completes all the software upgrades. The same process needs to be done on wyeast-lustre02 and wyeast-lustre03. I probably should have umounted Lustre mounts before this process, but I didn’t. So after the reboot, Lustre wasn’t quite working. I had to fix it.
First, I had to fix the firewall again on the Lustre machines:
sudo iptables -F
Next, zfs (the file system used by Lustre) was messed up on wyeast-lustre01 and wyeast-lustre02.
The command:
zfs list
wasn’t working. It showed that zfs wasn’t loaded. So the first step is to do:
modprobe zfs
This loaded zfs. However, our zfs pools are missing. This command fixed that:
zpool import
This finds the zpools and allows them to be imported:
zpool import lustre-ost0/ost0
zpool import lustre-ost0/ost0
This loads the zfs pools, but I still need to remount the Lustre file system. This needs to be done on the object storage targets first (lustre02 and lustre03) before it is done on the metadata server (lustre01).
sudo mount -t lustre lustre-ost0/ost0 /lustre-ost0/ost0
sudo mount -t lustre lustre-ost1/ost1 /lustre-ost1/ost1
Lustre actually automounted correctly on Lustre03, so I didn’t have to fix anything. With the targets working, it was time to fix Lustre01:
mount -t lustre lustre-mgsmdt/mgsmdt /lustre-mgsmdt/mgsmdt
Mounting the Lustre file system starts the Lustre service and we are off to the races.
Back on the compute nodes, it wasn’t finding the Lustre mount on the head node. So I had to unmount and then remount Lustre.
First, when I tried to unmount Lustre, the file system was reported as busy. So I ran the following command the find the guilty processes:
sudo lsof +f -- /lustre
This gives me a list of processes that I was then able to kill off. After that:
sudo umount /lustre
Followed by:
sudo mount -t lustre 192.168.1.11@tcp:/lustre /lustre
Which worked! Although I hadn’t yet updated the Lustre client, it was still able to handle the updated Lustre server. The other nodes that didn’t have active shells attached to them didn’t have any trouble with the change; I didn’t even have to remount them; the file system just showed up without any trouble.
Next step is to update the software on the compute nodes. Similar process except somewhat easier since we don’t have to deal with zfs. I still want to limit the install to the particular Linux kernel and the “Lustre-client” repo. In this case, I had to download the rpms from rpmfind:
https://rpmfind.net/linux/rpm2html/search.php?query=kernel%28×86-64%29&submit=Search+…&system=&arch=
I downloaded RPMs for kernel, kernel-debug-devel, kernel-headers, kernel-tools, and kernel-tools-libs. This time, I remembered to unmount /lustre first. Then I installed the new kernel modules:
Then, to install them:
sudo yum localinstall kernel-3.10.0-1062.9.1.el7.x86_64.rpm kernel-debug-devel-3.10.0-1062.9.1.el7.x86_64.rpm kernel-headers-3.10.0-1062.9.1.el7.x86_64.rpm kernel-tools-3.10.0-1062.9.1.el7.x86_64.rpm kernel-tools-libs-3.10.0-1062.9.1.el7.x86_64.rpm
Next, update the Lustre client:
sudo yum repo-pkgs lustre-client update kmod-lustre-client.x86_64 lustre-client.x86_64
Then update everything else, excluding the kernel stuff:
sudo yum update -x kernel,kernel-debug-devel,kernel-headers,kernel-tools,kernel-tools-libs
Finally, reboot and then remount Lustre:
sudo mount -t lustre 192.168.1.11@tcp:/lustre /lustre
Unlike with the Lustre server, I didn’t encounter any trouble with the reboot. The Lustre partition survived the update just fine, and I was able to successfully update all the rest of the installed software on the system.
Philosophy is the discipline that studies fundamental and universal questions, including existence, cognition, values, reason, and language. It covers many topics and problems, ranging from ethics and political figures to metaphysics and logic. Here are principal aspects of philosophy:
1. Definition of Philosophy
Philosophy comes from the Greek words “philos” (love) and “sophia” (wisdom). It is the desire to understand and make sense of the world around us and our place in it.
2. The Main branches of philosophy
– Ontology the study of the essence of being and existence.
– Epistemology the study of the nature and limits of knowledge.
– Ethics the analysis of moral principles and concepts of good deed and evil.
– Logic the study of the forms and principles of correct thinking.
– Political philosophy the study of questions of power, justice and the state.
3. Famous Philosophers
In the course of the history of philosophy, many thinkers have made meaningful contributions to this science. Some of the most famous include:
– Socrates, considered the founder of Western philosophy.
– Plato, a student of Socrates, developed the doctrine of forms.
– Aristotle, the creator of logic and a large number of scientific fields.
– Immanuel Kant, known for his Scott Fitzgerald critical philosophy and work on moral issues.
4. The Relevance of Philosophy in the Modern World
Philosophy remains relevant in the modern world because it helps people to understand difficult social and ethical issues, also develops critical thinking. It influences the legal system, politicians, and various fields of science.
5. Practical Applications of Philosophy
Philosophical ideas enter daily life. Ethical reflection helps people do the right thing in complex situations, and philosophical analysis contributes to better understanding of issues related to technology, art, and social justice.
Philosophy is not only an academic discipline, yes and method of thinking assists us to understand life’s complexities and make informed choices.
Philosophy is the discipline that studies major and universal questions, including existence, knowledge, values, reason, and language. It encompasses a vast number of topics and issues, from ethics and political figures to metaphysics and logic. Here are principal aspects of philosophy:
1. Definition of Philosophy
Philosophy comes from the Greek words “philos” (love) and “sophia” (wisdom). It is the desire to realize and make sense of the world around us and our place in it.
2. The Main branches of philosophy
– Ontology research of the essence of being and existence.
– Epistemology the study of the nature and limits of cognition.
– Ethics the analysis of moral principles and concepts of good deed and evil.
– Logic the study of the forms and principles of correct thinking.
– Socio-political philosophy the study of questions of power, justice and the state.
3. Eminent Philosophers
In the course of the history of philosophy, many thinkers have made significant contributions to this science. Some of the most famous include:
– Socrates, considered the progenitor of Western philosophy.
– Plato, a pupil of Socrates, developed the doctrine of forms.
– Aristotle, the creator of logic and a huge number of scientific fields.
– Immanuel Kant, known for his own Marcel Proust critical philosophy and work on moral issues.
4. The Relevance of Philosophy in the Modern World
Philosophy remains urgent in the modern world since enables people to understand complex social and moral issues, also develops critical thinking. It influences the legal system, politicians, and different fields of science.
5. Practical Applications of Philosophy
Philosophical ideas enter everyday life. Ethical reflection helps people do the right thing in difficult situations, and philosophical analysis contributes to best understanding of issues related to technology, art, and social justice.
Philosophy is including an academic discipline, as well as method of thinking assists us to understand life’s complexities and make informed choices.
Philosophy is the discipline that studies fundamental and universal questions, including existence, cognition, values, reason, and language. It encompasses a vast number of topics and problems, ranging from ethics and political figures to metaphysics and logic. Here are principal nuances of philosophy:
1. Definition of Philosophy
Philosophy comes from the Greek words “philos” (love) and “sophia” (wisdom). It is zeal to understand and make sense of the world around us and our place in it.
2. The Main branches of philosophy
– Ontology research of the essence of being and existence.
– Epistemology the study of the nature and limits of cognition.
– Ethics the analysis of moral principles and concepts of good and evil.
– Logic the study of the forms and principles of correct thinking.
– Political philosophy the study of questions of power, justice and the state.
3. Eminent Philosophers
Throughout the history of philosophy, many thinkers have made meaningful contributions to this science. Some of the most recognizable include:
– Socrates, considered the progenitor of Western philosophy.
– Plato, a student of Socrates, developed the doctrine of forms.
– Aristotle, the creator of logic and many of scientific fields.
– Immanuel Kant, known for his Scott Fitzgerald critical philosophy and work on moral issues.
4. The Relevance of Philosophy in the Modern World
Philosophy remains urgent in the modern world as enables people to understand complex social and ethical issues, also develops critical thinking. It affects the legal system, politicians, and different fields of science.
5. Practical Applications of Philosophy
Philosophical ideas penetrate everyday life. Ethical reflection helps people do the right thing in difficult situations, and philosophical analysis contributes to better understanding of problems related to technology, art, and social justice.
Philosophy is including an academic discipline, but also method of thinking assists us to understand life’s complexities and make informed choices.