K8s initializing the master & worker node error [How to Solve]

Error 1:coredns:1.8.0 Solution

Error 2:bridge-nf-call-iptables does not exist Solution
ip_forward contents are not set to 1Solution

CentOS 7.8

Error 1:

[config/images] Pulled registry.aliyuncs.com/k8sxio/pause:3.2
[config/images] Pulled registry.aliyuncs.com/k8sxio/etcd:3.4.13-0
failed to pull image “swr.cn-east-2.myhuaweicloud.com/coredns:1.8.0”:
output: time=“2021-04-30T13:26:14+08:00” level=fatal msg=“pulling
image failed: rpc error: code = NotFound desc = failed to pull and
unpack image “swr.cn-east-2.myhuaweicloud.com/coredns:1.8.0”:
failed to resolve reference
“swr.cn-east-2.myhuaweicloud.com/coredns:1.8.0”:
swr.cn-east-2.myhuaweicloud.com/coredns:1.8.0: not found”, error: exit
status 1 To see the stack trace of this error execute with –v=5 or
higher

coredns:1.8.0
failed to resolve reference \"swr.cn-east-2.myhuaweicloud.com/coredns:1.8.0\"
Solution:

curl -sSL https://kuboard.cn/install-script/v1.20.x/init_master.sh | sh -s 1.20.6 /coredns

Error 2:

[config/images] Pulled
swr.cn-east-2.myhuaweicloud.com/coredns/coredns:1.8.0
Initialize Master Node [init] Using Kubernetes version: v1.20.6 [preflight]
Running pre-flight checks error execution phase preflight: [preflight]
Some fatal errors occurred: [ERROR
FileContent–proc-sys-net-bridge-bridge-nf-call-iptables]:
/proc/sys/net/bridge/bridge-nf-call-iptables does not exist [ERROR
FileContent–proc-sys-net-ipv4-ip_forward]:
/proc/sys/net/ipv4/ip_forward contents are not set to 1

bridge-nf-call-iptables does not exist
[ERROR FileContent--proc-sys-net-bridge-bridge-nf-call-iptables]: /proc/sys/net/bridge/bridge-nf-call-iptables does not exist
Solution:
Execute in root：

modprobe br_netfilter

ip_forward contents are not set to 1
[ERROR FileContent--proc-sys-net-ipv4-ip_forward]: /proc/sys/net/ipv4/ip_forward contents are not set to 1
Solution:
ip_forward contents is not set to 1. View contents.

cat /proc/sys/net/ipv4/ip_forward
0

0 means prohibit
1 means forward
Modify

echo "1" > /proc/sys/net/ipv4/ip_forward

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