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zerotier website url

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zerotier how to

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kubernetes

September 12, 2023 · 9 min read

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名称规划

想好 ClusterName：比如:prod,prod1,dev,p,d,....
apiserver的ha domain: k8s<ClusterName>ce k8sprod1ce
规划好这个domain的static ip
ctrlNode(cNode)的hostname: k8s<ClusterName>c<number> k8sprod1c1 k8sprod1c2 k8sprod1c3
workNode(wNode)的hostname: k8s<ClusterName>w<letter> k8sprod1wa k8sprod1wb k8sprod1wc
k8s会使用机器的hostname作为节点名

搭建步骤。

在域名系统映射好apiserver的ha domain的固定静态ip
cNode1搭建：k8s_init_controlnode k8sprod1ce k8sprod1c1
- 搭建首个k8s control节点,开发环境可以只有一个cNode
- k8s_init_controlnode会解析出k8sprod1ce的static ip,设置好hostname,并搭建haproxy和keepalived
- 然后会用kubeadm init进行cluster的首次初始化
- 自动echodo kubectl apply -f https://raw.githubusercontent.com/flannel-io/flannel/master/Documentation/kube-flannel.yml
- 会生成~/join.txt保存下其他node(cNode or wNode)的join命令
- 运行完以后可以执行reload命令，shell会自动更新环境信息确保cmd下kubectl可用
- kubectl get nodes确保首个node is Ready
cNode2,3搭建：k8s_init_controlnode k8sprod1ce k8sprod1c2
- dev环境可以不用cNode2,3
- 这个只会准备hostname,haproxy和keepalived
- 然后找到初始节点的~/join.txt中的cNode join命令粘贴执行
wNode join
- 先sethostname正确配置好hostname
- 粘贴wNode的join命令加入

注意事项

remember word

taint cordon/uncordon

containerd arch layout

cmd runtime( runc, crun)
daemon runtime( containerd+ctr ) How to work with container images using ctr
image builder(buildah) Use Buildah to Build OCI Container Images
daemon image builder(buildkit+buildctl)
image regitry server(zot, docker regstry)
image pull/push(skopeo)
single mgr(nerdctl, docker)
cluster mgr(kubernetes+kubectl)
network(flannel, calico, )
network service mesh(linkerd2,)
https://blog.gmem.cc/cni-study-note
https://github.com/kubeedge/kubeedge huawei k8s (cloud edge, iot extend) opensource item

kubernetes port useage

port	module	desc
10250	kubelet	kubelet api
10248	kubelet	health check:healthz
10255	kubelet	kubelet readonly info api,can use without auth
4194	cAdvisor

kubernetes extends

operator Mygame is a sample kubernetes opeartor to manage 2048 game, contains crd, controller and webhook

kubernetes system oper

check ## memory section in NotesLinux.md
container images list: kubectl get nodes -o jsonpath='{range .items[\*]}{.metadata.name}{"\n"}{range .status.images[\*]}{"\t"}{.names[\0]}{"\n"}{end}{end}'
check system memory: cat /proc/meminfo | grep '^(MemFree:|Cached:|Shmem:|Buffers:|SReclaimable|Slab:)'
root cgroup check: cat /sys/fs/cgroup/memory.stat| grep '^(cache |rss |inactive_file |active_file |SReclaimable|Slab:)'
cgroup memory check
alias cgcheck='function cgcheck_fn() (cd /sys/fs/cgroup/$(cat /proc/$(pgrep ${1})/cgroup | sed "s@^[^/]*/@@") && echo pid:$(pgrep ${1}) && pwd && echo "can:cat memory.stat,exit,ls,..." && bash ); cgcheck_fn'
cgcreate and use by docker
cgcreate -g memory:test-docker-memory
docker run --cgroup-parent=/test-docker-memory --net=none -v /root/test_mem:/test -idt --name test --privileged csighub.tencentyun.com/admin/tlinux2.2-bridge-tcloud-underlay:latest
systemd sysemd
- systemctl == systemctl list-units
- systemctl -t slice
- systemctl -t service,masked
- systemctl list-unit-files
- systemd-cgls
- systemd-cgtop
control-plane-node-communication
- kubeadm缺省安装的已经设置好了 kubelet_node 通过证书信任 apiserver的client, 也就是这个文档中所的需要配置的地方 #只是新版本部署的anonymous-auth=false，client-ca-file这些配置都按照推荐都放到/var/lib/kubelet/config.yaml文件中了
- 如下配置让apiserver通过证书信任kubelet节点
- 生成统一的/etc/kubernetes/pki/kubelet-ca.{crt,key}
- apiserver --kubelet-certificate-authority /etc/kubernetes/pki/kubelet-ca.crt #
- 所有的node上的原有的selfsign(/var/lib/kubelet/pki/kubelet.{crt,key})替换为由 /etc/kubernetes/pki/kubelet-ca.{crt,key}签发的新crt,key
memory free > echo 3 > /proc/sys/vm/drop_caches && swapoff -a && swapon -a && printf ‘\n%s\n’ ‘Ram-cache and Swap Cleared’

certificate how to

kubeadm certs check-expiration
kubeadm certs renew all
#verify cert chain
openssl verify -CAfile /etc/kubernetes/pki/etcd/{ca.crt,ca.crt,healthcheck-client.crt,peer.crt,server.crt} #etcd-ca
openssl verify -CAfile /etc/kubernetes/pki/{front-proxy-ca.crt,front-proxy-ca.crt,front-proxy-client.crt} #front-proxy-ca
openssl verify -CAfile /etc/kubernetes/pki/{ca.crt,ca.crt,apiserver.crt,apiserver-kubelet-client.crt}
openssl verify -CAfile /var/lib/kubelet/pki/kubelet.crt{,}

`control pane certiciate(ca.{crt,key} etcd-ca.{crt,key} front-proxy-ca.{crt,key} sa.key sa.pub)`

upload to kube secret "kubeadm-certs"
upload is temp, will expire in 2 hour. this is use for add more control pane
kubeadm init phase upload-certs --upload-certs --certificate-key $(kubeadm certs certificate-key)
kubeadm init phase upload-certs --upload-certs #Upload control plane certificates to the kubeadm-certs Secret, and print out certificate-key
--certificate-key #define key by user option the encrypt key for uploaded cert. if not define. will auto generate new one and print out
can check it by: kubectl -n kube-system get secret kubeadm-certs -o yaml

#regenerate apiserver.crt with new certSANs item

#mv /etc/kubernetes/pki/apiserver.{crt,key} /tmp/
kubeadm init phase certs apiserver #this ok for most case
kubeadm init phase certs apiserver --config <(kubectl -n kube-system get configmap kubeadm-config -o jsonpath='{.data.ClusterConfiguration}'| sed 's@^apiServer:@&\n  certSANs:\n  - "ctrlpe.local"@')

#check certSAN for apiserver.crt openssl x509 -in=/etc/kubernetes/pki/apiserver.crt -text | grep -A 1 "Subject Alternative Name"

kube-apiserver url acess kubelet

  * kube-apiserver --kubelet-client-certificate=/etc/kubernetes/pki/apiserver-kubelet-client.crt --kubelet-client-key=/etc/kubernetes/pki/apiserver-kubelet-client.key
  *  --kubelet-certificate-authority=
  *  why kubelet serve cert need a certSANs(host list)

openssl x509 -req -days 365 -in server.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out server-cert.pem
echo subjectAltName = IP:worker_node_ip >? hostSANs_file.cnf
openssl x509 -req -days 365 -in server.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out server-cert.pem -extfile hostSANs_file.cnf

kubernetes debug utils

* journalctl -xe --unit kubelet
* kubectl describe nodes
* kubectl get nodes
* kubectl -n kube-public get cm cluster-info  -o yaml
* kubectl -n kube-system get cm kubeadm-config -o yaml
* kubectl cluster-info dump
* find ip define in kubernetes> grep -r '\.[0-9]\{1,3\}\/[0-9]\{1,2\}' /var/lib/kubelet/ /etc/kubernetes/
  kubectl logs podName | tail -f  /var/log/pods/kube-system_coredns-5dd5756b68-5wp4j_456bf805-a764-4874-b168-3c832d21241b/coredns/161.log

install k8s deps

 * systemd service file ref: github:kubespray: *.service.j2
 * let control-pane can get pod task(action like work pane):   kubectl taint nodes nodeName1 node-role.kubernetes.io/control-plane:NoSchedule-

install k8s

install k8s network plan

* pod ip range need be diff form service ip range
  * --pod-network-cidr @ kubeadm init --help
    * podSubnet @/etc/kubernetes/kubeadm-config.yaml
    * cluster-cidr: @/etc/kubernetes/kubeadm-config.yaml
    * clusterCIDR @/etc/kubernetes/kubeadm-config.yaml
  * --service-cidr @ kubeadm init --help #(default "10.96.0.0/12")
    * serviceSubnet @/etc/kubernetes/kubeadm-config.yaml 
    * serviceSubnet @kubectl -n kube-system get cm kubeadm-config -o yaml
    * --service-cluster-ip-range @/etc/kubernetes/manifests/kube-apiserver.yaml

mkdir -p -m 755 /etc/apt/keyrings
sudo apt-get update
sudo apt-get install -y apt-transport-https ca-certificates curl
curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.28/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
echo 'deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.28/deb/ /' | sudo tee /etc/apt/sources.list.d/kubernetes.list
sudo apt-get update
sudo apt-get install -y kubelet kubeadm kubectl
sudo apt-mark hold kubelet kubeadm kubectl
systemctl stop kubelet

config file list(ls /var/lib/kubelet/ /etc/kubernetes/manifests/ /etc/kubernetes /etc/cni/net.d/)

/etc/kubernetes:
admin.conf  calico-crb.yml  controller-manager.conf  kubeadm-config.yaml  manifests
calico-ipamconfig.yml  kubeadm-images.yaml  kubelet.env  node-crb.yml  ssl
calico-config.yml  calico-node-sa.yml  k8s-cluster-critical-pc.yml  kubelet-config.yaml  kubernetes-services-endpoint.yml  pki  tmp
calico-cr.yml  calico-node.yml  kdd-crds.yml  kubelet.conf  kubescheduler-config.yaml  scheduler.conf

/etc/kubernetes/manifests/:
etcd.yaml  kube-apiserver.yaml	kube-controller-manager.yaml  kube-scheduler.yaml

/var/lib/kubelet/:
config.yaml  cpu_manager_state	device-plugins	kubeadm-flags.env  memory_manager_state  pki  plugins  plugins_registry  pod-resources	pods

/etc/cni/net.d/:
10-calico.conflist  calico-kubeconfig  calico.conflist.template  nerdctl-bridge.conflist  nerdctl-dkfile_default.conflist  nerdctl-prometheus-pushgateway_default.conflist  nerdctl-rtorrent_default.conflist

cat /etc/cni/net.d/10-containerd-net.conflist
{
  "cniVersion": "1.0.0",
  "name": "containerd-net",
  "plugins": [
    {
      "type": "bridge",
      "bridge": "cni0",
      "isGateway": true,
      "ipMasq": true,
      "promiscMode": true,
      "ipam": {
        "type": "host-local",
        "ranges": [
          [{
            "subnet": "10.244.0.0/16"
          }],
          [{
            "subnet": "2001:4860:4860::/64"
          }]
        ],
        "routes": [
          { "dst": "0.0.0.0/0" },
          { "dst": "::/0" }
        ]
      }
    },
    {
      "type": "portmap",
      "capabilities": {"portMappings": true}
    }
  ]
}

grep -r 'kind: .' /etc/kubernetes/ | sort | uniq

/etc/kubernetes/admin.conf:kind: Config
/etc/kubernetes/calico-config.yml:kind: ConfigMap
/etc/kubernetes/calico-cr.yml:kind: ClusterRole
/etc/kubernetes/calico-crb.yml:  kind: ClusterRole
/etc/kubernetes/calico-crb.yml:- kind: ServiceAccount
/etc/kubernetes/calico-crb.yml:kind: ClusterRoleBinding
/etc/kubernetes/calico-ipamconfig.yml:kind: IPAMConfig
/etc/kubernetes/calico-node-sa.yml:kind: ServiceAccount
/etc/kubernetes/calico-node.yml:kind: DaemonSet
/etc/kubernetes/controller-manager.conf:kind: Config
/etc/kubernetes/k8s-cluster-critical-pc.yml:kind: PriorityClass
/etc/kubernetes/kdd-crds.yml:    kind: ""
/etc/kubernetes/kdd-crds.yml:    kind: BGPConfiguration
/etc/kubernetes/kdd-crds.yml:    kind: BGPPeer
/etc/kubernetes/kdd-crds.yml:    kind: BlockAffinity
/etc/kubernetes/kdd-crds.yml:    kind: CalicoNodeStatus
/etc/kubernetes/kdd-crds.yml:    kind: ClusterInformation
/etc/kubernetes/kdd-crds.yml:    kind: FelixConfiguration
/etc/kubernetes/kdd-crds.yml:    kind: GlobalNetworkPolicy
/etc/kubernetes/kdd-crds.yml:    kind: GlobalNetworkSet
/etc/kubernetes/kdd-crds.yml:    kind: HostEndpoint
/etc/kubernetes/kdd-crds.yml:    kind: IPAMBlock
/etc/kubernetes/kdd-crds.yml:    kind: IPAMConfig
/etc/kubernetes/kdd-crds.yml:    kind: IPAMHandle
/etc/kubernetes/kdd-crds.yml:    kind: IPPool
/etc/kubernetes/kdd-crds.yml:    kind: IPReservation
/etc/kubernetes/kdd-crds.yml:    kind: KubeControllersConfiguration
/etc/kubernetes/kdd-crds.yml:    kind: NetworkPolicy
/etc/kubernetes/kdd-crds.yml:    kind: NetworkSet
/etc/kubernetes/kdd-crds.yml:kind: CustomResourceDefinition
/etc/kubernetes/kubeadm-config.yaml:kind: ClusterConfiguration
/etc/kubernetes/kubeadm-config.yaml:kind: InitConfiguration
/etc/kubernetes/kubeadm-config.yaml:kind: KubeProxyConfiguration
/etc/kubernetes/kubeadm-config.yaml:kind: KubeletConfiguration
/etc/kubernetes/kubeadm-images.yaml:kind: ClusterConfiguration
/etc/kubernetes/kubeadm-images.yaml:kind: InitConfiguration
/etc/kubernetes/kubelet-config.yaml:kind: KubeletConfiguration
/etc/kubernetes/kubelet.conf:kind: Config
/etc/kubernetes/kubernetes-services-endpoint.yml:kind: ConfigMap
/etc/kubernetes/kubescheduler-config.yaml:kind: KubeSchedulerConfiguration
/etc/kubernetes/manifests/etcd.yaml:kind: Pod
/etc/kubernetes/manifests/kube-apiserver.yaml:kind: Pod
/etc/kubernetes/manifests/kube-controller-manager.yaml:kind: Pod
/etc/kubernetes/manifests/kube-scheduler.yaml:kind: Pod
/etc/kubernetes/node-crb.yml:  kind: ClusterRole
/etc/kubernetes/node-crb.yml:  kind: Group
/etc/kubernetes/node-crb.yml:kind: ClusterRoleBinding
/etc/kubernetes/scheduler.conf:kind: Config

kubectl get cm -n kube-system

coredns
extension-apiserver-authentication
kube-apiserver-legacy-service-account-token-tracking
kube-proxy #KubeProxyConfiguration
kube-root-ca.crt
kubeadm-config #ClusterConfiguration
kubelet-config #KubeletConfiguration

kubectl

kubectl [get|describe|edit|set resources] (pods,rc,services,cm,deployments,rs,runtimeclass|lease) -A

kubelet_reconfig

to learn more
kubectl edit cm -n kube-system kubelet-config
/var/lib/kubelet/config.yaml
systemctl restart kubelet

k8s usage

kubectl apply -f https://kubernetes.io/examples/controllers/frontend.yaml kubectl apply -f https://k8s.io/examples/admin/dns/dnsutils.yaml kubectl apply -f https://kubernetes.io/examples/pods/pod-rs.yaml kubectl apply -f https://k8s.io/examples/controllers/nginx-deployment.yaml

k8s config detail

kubeadm config(k8s_init_cfg&k8s_cluster_cfg helper)
- kubeadm config images list(use k8s_init_cfg gen k8s_cluster_cfg and get docker images(need use) list print out)
- kubeadm config images pull
- kubeadm config print [init-defefault|join-defaults|reset-default]
kubeadm kubeconfig(kube_access_cfg helper)
kube_access_cfg(--kubeconfig): include info(CACert,APIServer,ClientName,TokenAuth,ClientCertAuth)
- load kube_access_cfg: kubeadm&kubectl default load it from: ~/.kube/config or /etc/kubernetes/admin.conf
- save kube_access_cfg when boot init: kubeadm init will generate /etc/kubernetes/admin.conf at 'phase kubeconfig', reference kubeadm init -h
- send&cp /etc/kubernetes/admin.conf to some user's ~/.kube/config, will give full acesss the k8s cluster to this user
- generate kube_access_cfg(with limit acesss& validity-perio) print to stdout by cmd: kubeadm kubeconfig user [--config k8s_cluster_cfg.yml]
- (kubeadm config|kubeadm upgrade|...) can use --kubeconfig kube_access_cfg.yml option to load kube_access_cfg
k8s_init_cfg(--config):
- show default k8s_init_cfg: kubeadm config print init-defaults
- save default k8s_init_cfg: kubeadm config print init-defaults > k8s_init_cfg.yml
- on other machine k8s init by: kubeadm init --config k8s_init_cfg.yml
- 'kubeadm init' == 'kubeadm init --config <(kubeadm config print init-defaults)', but you can edit output of 'kubeadm config print init-defaults' for custom init
k8s_cluster_cfg:
- show current k8s_cluster_cfg: kubectl describe -n kube-system cm kubeadm-config
kubelet config:
- [kubeadm init|join|upgrade] will write KubeletConfiguration to file /var/lib/kubelet/config.yaml and passing it to the local node kubelet #ref
- kubelet all node update: ref: Update the cgroup driver on all nodes
- kubectl drain [node-name] --ignore-daemonsets
- kubectl uncordon [node-name]

route_command

July 12, 2023 · 2 min read

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important

use "ip route" instead of "route"
use "nft" & ufw instead of "iptables" #https://wiki.nftables.org/wiki-nftables/index.php/Main_Page

all

route != ip route
ip route is more powerful & and support in future
route will be replaced in future
ip route #show list
route #show list
0.0.0.0/0 mean default route
0.0.0.0/1 + 128.0.0.0/1 can override effeact default route, but not need to delete system origin default route

debian(linux)

ip route add 0/0 via 192.168.1.1
route add 10.2.100.0 mask 255.255.255.0 192.168.2.230
#/usr/sbin/ip -6 addr add '2402:4e00:1701:ea00:0:98f9:46b2:d3d3/64' dev eth0
#/usr/sbin/ip -6 route add default via 2402:4e00:1701:ea00::0 dev eth0

busybox(openwrt, alpine)

openwrt: iproute == ip route

iproute del local $IPV6ADDR  dev eth0
iproute add local $IPV6ADDR  dev eth0
route add -net 10.0.0.0/8 dev eth0.2 gw 192.168.2.6
route del default
route delete -net 45.78.6.36 netmask 255.255.255.255
route add default gw 192.168.1.1
route add default gw 192.168.1.1 dev br-lan
route add default dev wireguard

macosx

show netstat -nr

-n:(show ip or show name)
sudo route -n delete -net 0.0.0.0
sudo route -n add -net 0.0.0.0 192.168.1.1
sudo route -n add -net 0.0.0.0 192.168.123.198
sudo route -n add -net 10.2.100.0 192.168.2.230  255.255.255.0
sudo route -n delete -net 10.2.100.0

win

ipconfig /flushdns

others

ifconfig eth0 192.168.1.67/24
echo "nameserver 61.139.2.69" > /etc/resolv.conf

telecom

July 8, 2023 · 3 min read

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telecom (abbreviation/ acronym/ initialism )

RAN: Radio Access Network
UE:User Equipment //mobile phone
Node B:Radio base station
gNB:(Next Generation NodeB) //5g Base Station
eNB: //Base Station
NR: New Radio //5G radio interface between UE&gNB
5GCN:5G core network
EPC:Evolved Packet Core //4G LTE core network
UPF - User Plane Function
GTP(GPRS Tunnelling Protocol) //https://github.com/free5gc/gtp5g
AMF:Access and Mobility Management
3GPP:the Third-Generation Partnership Project //telecom stardard orgnazation
PLMN Identity(Mobile Country Code (MCC), Mobile Network Code (MNC) and a cell ID)
mobile identity (IMSI)

telcom abbrev map

https://www.5g-networks.net/5g-technology/5g-terminology-the-gnb/

Generation	Radio Technology	Base Station Name
2G	GSM	BTS (Base Transceiver Station)
3G	UMTS	NodeB
4G	LTE	eNB, Evolved NodeB
5G	NR:New Radio	gNB, Next Generation NodeB

aritech view

http://anisimoff.org/eng/5g/5g_overview.html

Spectrum usage & feature

ref http://anisimoff.org/eng/5g/5g_overview.html
Low-frequency bands < 3GHz 带宽低于20MHz, 长距离覆盖,稳定,低带宽
Medium-frequency bands （3-6Ghz）cmW 厘米波用多天线传输提高覆盖面高带宽200MHz 5G的主要使用频段
high-frequency bands,(6-24Ghz) mmW 毫米波，也是wifi使用的波段，5G也开始使用
Massive MIMO and Beamforming()
Diversity(frequency diversity) 单天线对,多频同传,不是所有频段都受到干扰,提高传输成功率 //Frequency diversity employs a single transmit/receive antenna pair, but operating at two or more widely spaced carrier frequencies.
Spatial Multiplexing 空间复用, 多数据流复用同一通道
Directivity (beamforming) 方向性波束,多天线服务不同方向互补干扰,提高覆盖率和抗干扰能力

google search

SIM aes128 MILENAGE

Secret & Auth

USIM have(AMF:Authentication Management Field,OPc:network operators key,LTE key Ki， IMSI：)
https://medium.com/uw-ictd/lte-authentication-2d0810a061ec
https://blog.magmaindia.org/2022/11/18/magma-milenage/
基于free5gc+UERANSIM 5G模拟环境的5G_AKA协议解析
https://nickvsnetworking.com/confidentiality-algorithms-in-3gpp-milenage-xor-comp128/
安全芯片(CPU卡芯片COS|读写器芯片|mPos芯片|USB-key芯片)
2020年中国智能安全芯片行业概览 //eSim与5G超级芯片
特种集成电路领军企业 //THD89/THC20/THC80 ST4SIM
抱紧你的SIM卡—5G物理安全初探 //相关性功耗分析（Correlation Power Analysis, CPA）//SIM卡的侧信道信息泄露
破解一张智能卡，需要多少步 //mifare芯片 //Henryk Plotz和Karsten Nohl发现随机数发生器的规律
Open On-Chip Debugger openpcd&picc //Proximity Integrated Circuit Cards (PICC) Proximity Coupling Devices (PCD)
eSIM LPA (Local Profile Assistant) for android //System privilege required.
Local Profile Assistant LPA Simulator

opensource

math words

July 2, 2023 · One min read

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Mean and average

https://stats.stackexchange.com/questions/14089/what-is-the-difference-between-mean-value-and-average/

The mean most commonly refers to the arithmetic mean, but may refer to some other form of mean, such as harmonic or geometric (see the Wikipedia article). Thus, when used without qualification, I think most people would assume that "mean" refers to the arithmetic mean.
Average has many meanings, some of which are much less mathematical than the term "mean". Even within the context of numerical summaries, "average" can refer to a broad range of measures of central tendency.
Thus, the arithmetic mean is one type of average. Arguably, when used without qualification the average of a numeric variable often is meant to refer to the arithmetic mean.

util-urls

June 27, 2023 · One min read

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https://github.com/inverse-inc/packetfence/issues/6195
generate_204 list ref https://bbs.itzmx.com/thread-96457-1-1.html

support ipv6 china

http://cp.cloudflare.com/generate_204
https://img.alicdn.com/a 
https://img.alicdn.com/b 
https://img.alicdn.com/c 
https://img.alicdn.com/d
https://img.alicdn.com/e
https://img.alicdn.com/generate_204
https://img.alicdn.com/test #response.body == test

china

https://i.ytimg.com/generate_204
https://connectivitycheck.platform.hicloud.com/generate_204
https://connectivitycheck.platform.hihonorcloud.com/generate_204
http://wifi.vivo.com.cn/generate_204
http://connectivitycheck.cbg-app.huawei.com/generate_204
http://connect.rom.miui.com/generate_204


https://www.google.com/gen_204
https://www.google.com/generate_204
https://www.v2ex.com/generate_204
http://www.qualcomm.cn/generate_204
http://www.gstatic.com/generate_204
http://clients3.google.com/generate_204
http://www.apple.com/library/test/success
http://connectivitycheck.android.com/generate_204
http://connectivitycheck.gstatic.com/generate_204
http://fireoscaptiveportal.com/generate_204
http://freetimecaptiveportal.com/generate_204
http://gateway.zscalerthree.net/generate_204
http://gateway.zscloud.net/generate_204
http://g.cn/generate_204
http://play.googleapis.com/generate_204
http://speedtest-global.spatialbuzz.net/generate_204
http://tabletcaptiveportal.com/generate_204
http://www.google.cn/generate_204
http://www.msftncsi.com/ncsi.txt
http://captive.roku.com/ok
http://www.appleiphonecell.com
http://captive.apple.com
http://detectportal.firefox.com/success.txt
http://www.msftconnecttest.com/connecttest.txt
http://www.youtube.com/generate_204
https://translate.google.cn/generate_204

big file download test

https://gw.alicdn.com/bao/uploaded/LB1bC41LVXXXXcGXFXXXXXXXXXX.mp4
http://steamusercontent-a.akamaihd.net/rangecheck   2M
https://cdn.akamai.steamstatic.com/steam/apps/5952/movie_max.webm
https://cdn.cloudflare.steamstatic.com/steam/apps/5952/movie_max.webm

ai-learn

June 26, 2023 · 2 min read

Spark light

Left

refs site

To remember

one-hot encoding
torch.nn.Liner
torch.nn.Embedding

torch.tensor([[1,2,4,5]])
weights = torch.rand(10, 3)
net = torch.nn.liner(10,2)
print(net,net.h)
torch.mm

AI > machine learning > deep learning

pytorch.nn.Embedding

理解Epoch, Batch, and Mini-batch

Gradient Descent
Batch Gradient Descent
Stochastic Gradient Descent
Mini-Batch Gradient Descent
比如有个2000个sample
将2000个sample整体一次性输入 (input net train&backward feedback) 就是Batch Gradient Descent
2000个数据one by one共2000次分别(input net train&backward feedback) 就是 stochastic gradient descent
2000个数据份 n组每组2000/n个sample(input net train&backward feedback) 就是Mini-Batch Gradient Descent
上面三个方式，一次整体sample train完称为一个epoch
要经过多次epoch才能达到(Gradient Descent)剃度下降效果

similarity相似度 | diversity index多样性指数

Cosine similarity #向量i和j之间的向量夹角大小越小越相似
Pearson Correlation Coefficient(皮尔逊相关系数) #与余弦相似度相比,加入了用户平均分对各独立评分进行修正,减小了用户评分偏置的影响
Euclidean Distance #m维空间中两点之间的距离
Jaccard Index(Jaccard similarity coefficient) #两个集合A和B的交集在其二者的并集中所占的比例
Jaccard Distance #两个集合中不同元素占所有元素的比例来衡量两个集合的区分度

名称规划​

搭建步骤。​

注意事项​

remember word​

containerd arch layout​

kubernetes port useage​

kubernetes extends​

kubernetes system oper​

certificate how to​

control pane certiciate(ca.{crt,key} etcd-ca.{crt,key} front-proxy-ca.{crt,key} sa.key sa.pub)​

kubernetes debug utils​

install k8s deps

install k8s

install k8s network plan​

config file list(ls /var/lib/kubelet/ /etc/kubernetes/manifests/ /etc/kubernetes /etc/cni/net.d/)

kubectl

kubelet___reconfig__

k8s usage

k8s config detail

important​

all​

debian(linux)​

busybox(openwrt, alpine)​

macosx​

win​

others​

telecom (abbreviation/ acronym/ initialism )​

telcom abbrev map​

aritech view​

Spectrum usage & feature​

google search​

Secret & Auth​

opensource​

Mean and average​

support ipv6 china

china

big file download test

refs site

To remember

AI > machine learning > deep learning​

pytorch.nn.Embedding​

理解Epoch, Batch, and Mini-batch​

similarity相似度 | diversity index多样性指数​

名称规划

搭建步骤。

注意事项

remember word

containerd arch layout

kubernetes port useage

kubernetes extends

kubernetes system oper

certificate how to

`control pane certiciate(ca.{crt,key} etcd-ca.{crt,key} front-proxy-ca.{crt,key} sa.key sa.pub)`

kubernetes debug utils

install k8s network plan

kubelet_reconfig

important

all

debian(linux)

busybox(openwrt, alpine)

macosx

win

others

telecom (abbreviation/ acronym/ initialism )

telcom abbrev map

aritech view

Spectrum usage & feature

google search

Secret & Auth

opensource

Mean and average

AI > machine learning > deep learning

pytorch.nn.Embedding

理解Epoch, Batch, and Mini-batch

similarity相似度 | diversity index多样性指数