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== Pytorch FAQ ==
{{Status
|status=Draft
|owner=Knowledge Agent
|last_update=2026-07-16
|review=Pending
}}


* How to get [[CUDA]] compute capability of a GPU?
{{TOC}}
** $python -c "import torch; print(torch.cuda.get_arch_list())"


== Show List Of Network Cards on Linux ==
== Overview ==


* <kbd>lspci command</kbd> : List all PCI devices.
FAQ에 대한 기술 문서입니다.
** <code>'''#lspci | egrep -i --color 'network|ethernet''''</code>
** <code>'''#lspci | egrep -i --color 'network|ethernet|wireless|wi-fi''''</code>


* <kbd>lshw command</kbd> : [[Linux]] identify Ethernet interfaces and NIC hardware.
=== Summary ===
** <code>'''#lshw -class network'''</code>
** '''$sudo lshw -class network -short'''


* <kbd>dmidecode command</kbd> : List all hardware data from BIOS.
* 무엇인가? - FAQ
* <kbd>ifconfig command</kbd> : Outdated network config
* 왜 필요한가? - HPC 및 서버 환경에서 필수 개념
** <code>'''$ifconfig -a'''</code>
* 언제 사용하는가? - 서버 구성, 성능 튜닝, 문제 해결 시
** <code>'''$ip link show'''</code>
** <code>'''$ip a'''</code>


* <kbd>ip command</kbd> : Recommended new network config .
** <code>'''$ip a show wlp82s0'''</code>
** <code>'''$ip -br -c link show'''        # To list all interface, link status, MAC address, etc</code>
** <code>'''$ip -br -c addr show'''        # similar list with IP address instead of MAC Address</code>


* <kbd>hwinfo command</kbd> : Probe Linux for network cards.
== Purpose ==
** <code>'''$sudo hwinfo --network --short'''</code>


* <kbd>ethtool command</kbd> : See NIC/card driver and settings on Linux.
이 문서가 존재하는 이유
** <code>'''$sudo ethtool -i eno1'''</code>
** <code>'''$sudo ethtool -i enp0s31f6'''</code>


* /proc/net/dev file - The dev pseudo-file contains network device status information. This gives the number of received and sent packets, the number of errors and collisions and other basic statistics
* Goal: FAQ에 대한 기술 정보 제공
** <code>'''$cat /proc/net/dev'''</code>
* Scope: FAQ의 개념, 사용법, 설정
* Non-goals: 다른 주제로의 확장


=== Failed to set iommu for container: Invalid argument ===


== Key Concepts ==


A VM configured with a vGPU that supports SR-IOV may fail to start, This issue occurs because PCIe [[AER (Advanced Error Reporting)]] [[support]] was disabled in the [[BIOS]] settings of the server.
{| class="wikitable"
! Concept
! Description
! Related
|-
| FAQ
| HPC/서버 환경에서 중요한 기술 개념
| [[Linux]], [[Server]]
|}
 
 
== Detailed Explanation ==
 
If your system reboot randomly without [[kernel]] logs, the most possible reason would be power supply stability issue although the PSU might looks working well.
Beyond PSU, we can trace the reason of system reboot to software issue or hardware issue with kernel.panic parameters, 
If kernel.panic system parameter is <code>0,</code> it is turned off automatic reboot on panic, any other value is the number of seconds it wait before reboot.
With <code>sysctl -w kernel.panic=0</code> you would turn it off, if it is not already off.
If this is set to <code>0</code> and your server still reboots itself,  it would really think this is a hardware issue. If this stops the automatic rebooting, then we know the reboot is caused by a watchdog timer or other software issue
* Reason - warning or information from the snapshotter<ref>https://dev.to/napicella/what-is-a-containerd-snapshotters-3eo2</ref> - image storage - that we have a lot of choices
* Impact : the warning log doesn't impact the whole system operating
* Solve to
1.Disable the snapshotter plugins which you don't need by updating config file for your system and restart containerd, like
<# /etc/containerd/config.toml
disabled_plugins = ["cri", "btrfs"]
2. To use ZFS, you need to mount ZFS dataset on  /var/lib/containerd/io.containerd.snapshotter.v1.zfs
3. To use btrfs, you need to mount btrfs to /var/lib/containerd/io.containerd.snapshotter.v1.btrfs
4. For aufs, you need to modprobe it as explained in the error log
* Reason - no nvidia-container-toolkit or currupt exist package
* Solve to install/reinstall nvidia-container-toolkit then restart [[docker]] daemon
<syntaxhighlight lang="bash">
$distribution=$(. /etc/os-release;echo $ID$VERSION_ID) \
    && curl -s -L https://nvidia.github.io/nvidia-docker/gpgkey | sudo apt-key add - \
    && curl -s -L https://nvidia.github.io/nvidia-docker/$distribution/nvidia-docker.list | sudo tee /etc/apt/sources.list.d/nvidia-docker.list
 
 
== Best Practices ==
 
* 최신 버전 사용 권장
* 공식 문서 참고
* 테스트 환경에서 먼저 검증
 
 
== References ==
 
* [https://wiki.hpcmate.com FAQ]
 
 
== Related Pages ==
 
* [[Linux]]
* [[Server]]
* [[Hardware]]
* [[Network]]
 
 
[[Category:Server]]
== Knowledge Graph ==
 
Related
 
→ [[Linux]]
→ [[Server]]
→ [[Troubleshooting]]
→ [[Terms]]
 
[[Category:Reference]]

Latest revision as of 11:28, 17 July 2026

Template:Status

Template:TOC

Overview

FAQ에 대한 기술 문서입니다.

Summary

  • 무엇인가? - FAQ
  • 왜 필요한가? - HPC 및 서버 환경에서 필수 개념
  • 언제 사용하는가? - 서버 구성, 성능 튜닝, 문제 해결 시


Purpose

이 문서가 존재하는 이유

  • Goal: FAQ에 대한 기술 정보 제공
  • Scope: FAQ의 개념, 사용법, 설정
  • Non-goals: 다른 주제로의 확장


Key Concepts

Concept Description Related
FAQ HPC/서버 환경에서 중요한 기술 개념 Linux, Server


Detailed Explanation

If your system reboot randomly without kernel logs, the most possible reason would be power supply stability issue although the PSU might looks working well. Beyond PSU, we can trace the reason of system reboot to software issue or hardware issue with kernel.panic parameters, If kernel.panic system parameter is 0, it is turned off automatic reboot on panic, any other value is the number of seconds it wait before reboot. With sysctl -w kernel.panic=0 you would turn it off, if it is not already off. If this is set to 0 and your server still reboots itself, it would really think this is a hardware issue. If this stops the automatic rebooting, then we know the reboot is caused by a watchdog timer or other software issue

  • Reason - warning or information from the snapshotter[1] - image storage - that we have a lot of choices
  • Impact : the warning log doesn't impact the whole system operating
  • Solve to

1.Disable the snapshotter plugins which you don't need by updating config file for your system and restart containerd, like

<# /etc/containerd/config.toml
disabled_plugins = ["cri", "btrfs"]

2. To use ZFS, you need to mount ZFS dataset on /var/lib/containerd/io.containerd.snapshotter.v1.zfs 3. To use btrfs, you need to mount btrfs to /var/lib/containerd/io.containerd.snapshotter.v1.btrfs 4. For aufs, you need to modprobe it as explained in the error log

  • Reason - no nvidia-container-toolkit or currupt exist package
  • Solve to install/reinstall nvidia-container-toolkit then restart docker daemon

<syntaxhighlight lang="bash"> $distribution=$(. /etc/os-release;echo $ID$VERSION_ID) \

   && curl -s -L https://nvidia.github.io/nvidia-docker/gpgkey | sudo apt-key add - \ 
   && curl -s -L https://nvidia.github.io/nvidia-docker/$distribution/nvidia-docker.list | sudo tee /etc/apt/sources.list.d/nvidia-docker.list


Best Practices

  • 최신 버전 사용 권장
  • 공식 문서 참고
  • 테스트 환경에서 먼저 검증


References


Related Pages

Knowledge Graph

Related

LinuxServerTroubleshootingTerms