My own proxy station deployed through Docker still request sum.golang.org when in use

[Tryanks]

My proxy is deployed on an accelerated server and can be accessed via https://go.XXXXX.com
Locally set:

go env -w GOPROXY=https://go.XXXXX.com,direct

When synchronizing projects with go mod tidy, each synchronization still takes a long time and fails after a period of time. Here is an excerpt from the logs:

(base) ~\GolandProjects\project git:[finish]
go mod tidy
go: downloading github.com/stretchr/testify v1.3.0
go: downloading github.com/google/pprof v0.0.0-20221118152302-e6195bd50e26
go: downloading modernc.org/ccgo/v4 v4.10.1
go: downloading modernc.org/fileutil v1.3.0
go: downloading github.com/davecgh/go-spew v1.1.1
go: project imports
        github.com/glebarez/sqlite imports
        github.com/glebarez/go-sqlite imports
        modernc.org/libc tested by
        modernc.org/libc.test imports
        modernc.org/ccgo/v4/lib: modernc.org/ccgo/v4@v4.10.1: verifying module: modernc.org/ccgo/v4@v4.10.1: Get "https://sum.golang.org/lookup/modernc.org/ccgo/v4@v4.10.1": dial tcp 142.251.43.17:443: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
go: project imports
        github.com/glebarez/sqlite imports
        github.com/glebarez/go-sqlite imports
        modernc.org/libc tested by
        modernc.org/libc.test imports
        modernc.org/fileutil/ccgo: modernc.org/fileutil@v1.3.0: verifying module: modernc.org/fileutil@v1.3.0: Get "https://sum.golang.org/lookup/modernc.org/fileutil@v1.3.0": dial tcp 142.251.43.17:443: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.

Everything works fine when using goproxy.cn.
I deployed directly using the default Docker command without changing any configuration options.

EDIT: Perhaps I can set GOSUMDB to off to disable the verification to solve this problem, but my issue is that this problem does not exist when using goproxy.cn. I hope to keep my site consistent with it.

[aofei]

but my issue is that this problem does not exist when using goproxy.cn

That's because goproxy.cn supports proxying the default checksum database sum.golang.org.

You can set it up on your Goproxy instance if needed. See https://pkg.go.dev/github.com/goproxy/goproxy#Goproxy.ProxiedSumDBs.