DNS Query Issue in Apline Image with MUSL libc

Until now I just know there're DNS issues in Apline image, which is major caused by musl libc. Check Racy conntrack and DNS lookup timeouts

All right, I know musl libc is different to gnu libc, usually user shouldn't feel differences in app level, but this definitely an user-aware issue.

1. glibc could be configured to send those requests sequentially, with single-request and single-request-reopen options, but musl cannot.

2. musl's resolver previously did not support the "domain" and "search" keywords in resolv.conf. This feature was added in version 1.1.13, but its behavior differs slightly from glibc's

The good news is query DNS sequentially is not the only one solution for netfilter race problem (UDP query would be dropped accidentally).

Refs:

• Functional differences from glibc - Name Resolver/DNS
• Why does musl make my Rust code so slow?
• 如何解决 Kubernetes 的 DNS 延迟问题 (Chinese)
• 记一次 k3s 的 dns 问题调查解决过程 (Chinese)
• Using NodeLocal DNSCache in Kubernetes Clusters
• Wener Wiki - musl (Chinese)