gravatar

很惭愧，就做了一点微小的工作

Dash

WorkingTipsOnRPISharingDesktop

Feb 12, 2021
Technology

无线接入点配置

1. 基本配置

树莓派4B 8G版本，刷入了Ubuntu 20.04.2 arm64版本：

ubuntu@rpi1:~$ cat /etc/issue
Ubuntu 20.04.2 LTS \n \l

ubuntu@rpi1:~$ uname -a
Linux rpi1 5.4.0-1028-raspi #31-Ubuntu SMP PREEMPT Wed Jan 20 11:30:45 UTC 2021 aarch64 aarch64 aarch64 GNU/Linux

2. 网络配置

默认Ubuntu20.04采用netplan作为网络配置方式，一般情况下满足网络配置需求，然而在配置无线接入点的时候，需要固定wlan0 IP地址的情况下，netplan配置就不能成功，因为它在配置wlan0 固定IP地址时需要配置ssid。因而我们采用传统的ifupdown作为网络配置手段:

关闭netplan配置:

# mv /etc/netplan/50-cloud-init.yaml /root

安装必要的软件:

# apt-get install -y resolvconf netctl ifupdown hostapd dnsmasq

配置网络:

# vim /etc/network/interfaces
    # Include files from /etc/network/interfaces.d:
    source-directory /etc/network/interfaces.d
    
    source /etc/network/interfaces.d/*
    
    auto lo
    iface lo inet loopback
    
    
    auto eth0
    iface eth0 inet dhcp
    
    auto wlan0
    iface wlan0 inet static  
        address 10.0.70.1
            netmask 255.255.255.0
# chmod 777 /etc/network/interfaces

现在重新启动树莓派，发现eth0配置成功，然而wlan0尚未配置， 我们通过在crontab中配置定时任务的方法来配置wlan0:

# crontab -e 
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin

@reboot sleep 120 && /usr/bin/systemctl restart networking

使能crontab:

# systemctl enable cron

3. hostapd配置

配置hostapd(/etc/hostapd/hostapd.conf):

# the interface used by the AP
interface=wlan0
driver=nl80211
# "g" simply means 2.4GHz band
hw_mode=g
# the channel to use
channel=10
# limit the frequencies used to those allowed in the country
ieee80211d=1
# the country code
country_code=CN
# 802.11n support
ieee80211n=1
# QoS support
wmm_enabled=1
# the name of the AP
ssid=rpiwifi
macaddr_acl=0
# 1=wpa, 2=wep, 3=both
auth_algs=1
ignore_broadcast_ssid=0
# WPA2 only
wpa=2
wpa_passphrase=xxxxxxxxxxxxx
wpa_key_mgmt=WPA-PSK
#wpa_pairwise=TKIP
rsn_pairwise=CCMP

编辑文件/etc/default/hostapd， 更改含有DAEMON_CONF的行为: DAEMON_CONF="/etc/hostapd/hostapd.conf".

然而此时hostapd在启动以后并不会重新启动，我们需要在crontab中添加其自动启动.

# crontab -e
@reboot sleep 120 && /usr/bin/systemctl restart networking  && systemctl restart hostapd

4. IP地址配置

此时hostapd无法给客户端配置IP地址，为此我们需要配置dnsmasq(/etc/dnsmasq.conf):

#配置监听地址
listen-address=127.0.0.1,10.0.70.1
#配置DHCP分配段
dhcp-range=10.0.70.50,10.0.70.150,12h
dhcp-option=3,10.0.70.1

5. iptables配置

编辑/etc/sysctl.conf并取消这一行的注释：

net.ipv4.ip_forward=1

为eth0出站流量添加伪装：

# sudo iptables -t nat -A  POSTROUTING -o eth0 -j MASQUERADE

我们调节crontab为:

@reboot sleep 30 && /usr/bin/systemctl restart networking  && systemctl restart hostapd && /usr/sbin/iptables -t nat -A  POSTROUTING -o eth0 -j MASQUERADE

到现在为止，我们应该可以配置出了一个随时可以访问internet的rpi接入点。

后续需要注意点

以该rpi为接入点，接入到某个网络中，然而该网络中的Internet是通过另台rpi的WIFI所共享的。

另台RPI上的无线连接通过wifi-menu来配置:

# apt-get install -y netctl

RPICluster

Feb 5, 2021
Technology

Flashing

Flash with following os:

root@ubuntu:/home/ubuntu# uname -a
Linux ubuntu 5.4.0-1028-raspi #31-Ubuntu SMP PREEMPT Wed Jan 20 11:30:45 UTC 2021 aarch64 aarch64 aarch64 GNU/Linux
root@ubuntu:/home/ubuntu# cat /etc/issue
Ubuntu 20.04.2 LTS \n \l

Disable auto update:

# systemctl stop apt-daily.timer;systemctl disable apt-daily.timer ; systemctl stop apt-daily-upgrade.timer ; systemctl disable apt-daily-upgrade.timer; systemctl stop apt-daily.service;  systemctl mask apt-daily.service; systemctl daemon-reload

Configure hostname:

# hostnamectl set-hostname rpi1
# hostnamectl set-hostname rpi2

Configure cn repository:

# vim /etc/apt/sources.list
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal main restricted universe multiverse
# deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal main main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-updates main restricted universe multiverse
# deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-updates main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-backports main restricted universe multiverse
# deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-backports main restricted universe multiverse
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-security main restricted universe multiverse
# deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ focal-security main restricted universe multiverse
# apt-get update -y

Install some packages:

# apt-get install -y net-tools virt-manager lxde tightvncserver sshpass ssh-askpass
# usermode -a -G kvm,libvirt  ubuntu

Configure vnc

# vncserver
# vim ~/.vnc/xstartup
	#!/bin/sh
	exec startlxde
# vncserver -kill :1
# vncserver

In vnc we could use virt-manager.

Install new os:

/images/2021_02_05_16_53_45_633x380.jpg

KubeQuickRun

Feb 3, 2021
Technology

Via following tips we could quickly run apps in k8s:

# kubectl create deployment xxxx --image=xxxx:16.04 -- sleep 3000
# kubectl get deployment
# kubectl get deployment xxxx -oyaml --export>kkk.yaml
# vim kkk.yaml
command: ["sleep"]
args: ["3600000"]
# kubectl delete -f kkk.yaml
# kubectl create -f kkk.yaml
# kubectl scale deployment xxxx -replicas=4

DirectlyEditDEB

Jan 25, 2021
Technology

项目中有时需要对DEB包做些许修改，譬如，在离线场景下某些DEB包的postinst中有需要用在线方式下载可执行文件的情况，这种情况下可以借助dpkg-deb的解包/压缩命令来临时修改出一个含有所有离线文件的包，举opennebula-node-firecracker的包为例说明。

opennebula-node-firecracker是用于在opennebula上运行轻量级VM firecracker的包，在线安装时它需要从github上拉取相应版本的firecracker及 jailer可执行文件，这让它在离线场景下无法安装成功。同时，因为它默认作为runtime的一种，其配置文件与opennebula-node-kvm里的某些配置文件相同，导致安装时无法继续，我们可以通过如下的方式修改此包，让其适配离线化安装。

准备

在线场景下下载该包，并拷贝到工作目录, 解压:

# cp /var/cache/apt/archives/opennebula-node-firecracker_5.12.0.3-1.ce_amd64.deb .
# mkdir tmp
# dpkg-deb -R opennebula-node-firecracker_5.12.0.3-1.ce_amd64.deb tmp/

主要目录结构如下:

├── DEBIAN
│   ├── conffiles
│   ├── control
│   ├── md5sums
│   ├── postinst
│   └── postrm
├── etc
│   ├── cron.d
│   │   └── opennebula-node
│   ├── sudoers.d
│   │   └── opennebula-node-firecracker
│   └── sysctl.d
│       └── bridge-nf-call.conf
├── srv
│   └── jailer
│       └── firecracker
└── usr
    ├── bin
    │   └── svncterm_server
    ├── sbin
    │   ├── install-firecracker
    │   ├── one-clean-firecracker-domain
    │   └── one-prepare-firecracker-domain
    └── share
        └── doc
            └── opennebula-node-firecracker
                ├── changelog.Debian.gz
                ├── copyright
                └── NEWS.Debian.gz

我们需要修改的要点如下:

1. DEBIAN/conffiles, 含有此包需写入的配置文件。
2. DEBIAN/md5sums, 含有可执行文件的md5校验码。
3. DEBIAN/postinst, 包安装完成后需执行的脚本。
4. etc/ 下是包安装后在主机上需添加的配置文件。
5. usr/bin, usr/sbin，主机上需拷入的可执行文件。

修改

观察DEBIAN/postinst中含有以下条目:

# cat DEBIAN/postinst 
#!/bin/sh

set -e

ONE_USER=oneadmin

if [ "$1" = "configure" ]; then
    # Install Firecracker + jailer
    /usr/sbin/install-firecracker

打开install-firecracker文件后观察其下载脚本为:

# cat usr/sbin/install-firecracker 
#!/bin/sh
....

# Download version version of Firecracker
curl -LOJ https://github.com/firecracker-microvm/firecracker/releases/download/${version}/firecracker-${version}-$(uname -m)
mv firecracker-${version}-$(uname -m) /usr/bin/firecracker
chmod +x /usr/bin/firecracker


# Download version version of jailer
curl -LOJ https://github.com/firecracker-microvm/firecracker/releases/download/${version}/jailer-${version}-$(uname -m)
mv jailer-${version}-$(uname -m) /usr/bin/jailer
chmod +x /usr/bin/jailer

这里我们直接干掉所有的curl及mv脚本，把预先下载好的firecracker/jailer文件拷贝到安装目录即可。

# tree ../tmp/usr
../tmp/usr
├── bin
+++ │   ├── firecracker
+++ │   ├── jailer
│   └── svncterm_server
├── sbin
│   ├── install-firecracker
.....

此外需要修改md5sums及干掉etc下重复的配置文件。而后压缩包。

压缩包

一条命令:

# dpkg-deb -b tmp opennebula-node-firecracker_5.12.0.3-1.ce_fixed_amd64.deb

检查新生成包的大小:

# ls -l -h *.deb
-rw-r--r-- 1 root root  24K Jan 25 09:06 opennebula-node-firecracker_5.12.0.3-1.ce_amd64.deb
-rw-r--r-- 1 root root 1.2M Jan 25 09:11 opennebula-node-firecracker_5.12.0.3-1.ce_fixed_amd64.deb

使用fixed后的包安装，此时可忽略internet下载过程，且解决了包安装时的冲突问题。

Usingdockerforbuildingkubeadm

Jan 21, 2021
Technology

X86 version kubeadm building process:

# docker run -it ubuntu:18.04 /bin/bash
# cat /etc/issue
Ubuntu 18.04.5 LTS \n \l
# apt-get update -y
# apt-get install -y wget unzip vim build-essential rsync
# wget https://github.com/kubernetes/kubernetes/archive/v1.19.7.zip
# wget https://golang.org/dl/go1.15.7.linux-amd64.tar.gz
# tar -C /usr/local -xzf go1.15.7.linux-amd64.tar.gz
# export PATH=$PATH:/usr/local/go/bin
# go version
go version go1.15.7 linux/amd64
# cd kubernetes-v1.19.7
# vim cmd/kubeadm/app/constants/constants.go
CertificateValidity = time.Hour * 24 * 365 * 100
#  vim vendor/k8s.io/client-go/util/cert/cert.go
func NewSelfSignedCACert
NotAfter: 	now.Add(duration365d * 100).UTC(),
func GenerateSelfSignedCertKeyWithFixtures
maxAge := 100 * time.Hour * 24 * 365
# make all WHAT=cmd/kubeadm
# _output/bin/kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"19", GitVersion:"v1.19.7", GitCommit:"1dd5338295409edcfff11505e7bb246f0d325d15", GitTreeState:"archive", BuildDate:"2021-01-21T07:15:36Z", GoVersion:"go1.15.7", Compiler:"gc", Platform:"linux/amd64"}
# cp _output/bin/kubeadm ..

Arm64 version kubeadm building process:

Edit files and make changes:

# vim hack/make-rules/cross.sh
    make all WHAT="${KUBE_SERVER_TARGETS[*]}" KUBE_BUILD_PLATFORMS="${KUBE_SERVER_PLATFORMS[*]}"
    
    #make all WHAT="${KUBE_NODE_TARGETS[*]}" KUBE_BUILD_PLATFORMS="${KUBE_NODE_PLATFORMS[*]}"
    #
    #make all WHAT="${KUBE_CLIENT_TARGETS[*]}" KUBE_BUILD_PLATFORMS="${KUBE_CLIENT_PLATFORMS[*]}"
    #
    #make all WHAT="${KUBE_TEST_TARGETS[*]}" KUBE_BUILD_PLATFORMS="${KUBE_TEST_PLATFORMS[*]}"
    #
    #make all WHAT="${KUBE_TEST_SERVER_TARGETS[*]}" KUBE_BUILD_PLATFORMS="${KUBE_TEST_SERVER_PLATFORMS[*]}"
#  vim hack/lib/golang.sh
    readonly KUBE_SUPPORTED_SERVER_PLATFORMS=(
    #  linux/amd64
    #  linux/arm
      linux/arm64
    #  linux/s390x
    #  linux/ppc64le
    )
    
    //.............
    
    kube::golang::server_targets() {
      local targets=(                       
      #  cmd/kube-proxy                                                        
      #  cmd/kube-apiserver                 
      #  cmd/kube-controller-manager                                 
      #  cmd/kubelet 
        cmd/kubeadm
      #  cmd/kube-scheduler
      #  vendor/k8s.io/apiextensions-apiserver
      #  cluster/gce/gci/mounter
      )

Build:

# make cross

v1.20.7 update

Have to change go version to v1.17 for building, also notice the memory usage.

apt-get update -y && apt-get install -y wget unzip vim build-essential rsync
wget https://github.com/kubernetes/kubernetes/archive/v1.20.7.zip
wget https://golang.org/dl/go1.17.linux-amd64.tar.gz
tar -C /usr/local -xzf go1.17.linux-amd64.tar.gz 
export PATH=$PATH:/usr/local/go/bin
go version
unzip v1.20.7.zip 
cd kubernetes-1.20.7/
vim cmd/kubeadm/app/constants/constants.go
vim vendor/k8s.io/client-go/util/cert/cert.go
make all WHAT=cmd/kubeadm
cp _output/bin/kubeadm ..