如何为 Route 53 私有托管区域解析带有“.local”后缀的域名？

简短描述

通过 systemd-resolved 服务的 Linux 操作系统发行版，使用存根解析器处理 DNS 查询。存根解析程序 IP 位于 /etc/resolv.conf。本地 DNS 存根侦听器不会转发带有“.local”后缀的域名的 DNS 请求。DNS 请求失败，并显示与以下输出类似的响应代码 “ServFail”：

### failed ###
ubuntu@ip-172-31-2-3:~$ dig example.local.

; <<>> DiG 9.18.1-1ubuntu1.1-Ubuntu <<>> example.local.
;; global options: +cmd
;; Got answer:
;; WARNING: .local is reserved for Multicast DNS
;; You are currently testing what happens when an mDNS query is leaked to DNS
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 29563    ### status: SERVFAIL ###
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;example.local.            IN    A

;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53) (UDP)            ### 127.0.0.53 is systemd-resolved ###
;; WHEN: Thu Jun 30 12:34:56 UTC 2022
;; MSG SIZE  rcvd: 42

### success ###
ubuntu@ip-172-31-2-3:~$ dig example.local. @172.31.0.2        ### dig to @172.31.0.2 AmazonProvidedDNS / Route 53 Resolver ###

; <<>> DiG 9.18.1-1ubuntu1.1-Ubuntu <<>> example.local. @172.31.0.2
;; global options: +cmd
;; Got answer:
;; WARNING: .local is reserved for Multicast DNS
;; You are currently testing what happens when an mDNS query is leaked to DNS
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29352    ### status: NOERROR ###
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;example.local.            IN    A

;; ANSWER SECTION:
example.local.        300    IN    A    192.0.2.1

;; Query time: 4 msec
;; SERVER: 172.31.0.2#53(172.31.0.2) (UDP)            ### 172.31.0.2 is AmazonProvidedDNS / Route 53 Resolver ###
;; WHEN: Thu Jun 30 12:34:56 UTC 2022
;; MSG SIZE  rcvd: 58

解决方法

要解析带有 “.local” 后缀的域名，请使用外部解析器而不是本地 DNS 存根侦听器。

**注意：**最好避免使用域名“.local”后缀，因为 RFC 6762 将此域名专供Multicast DNS 使用。

1.    将 DNS 解析器从本地 DNS 存根侦听器更改为外部 DNS 解析器（AmazonProvidedDNS）。

cd /etc/
sudo ln -sf ../run/systemd/resolve/resolv.conf

2.    更改 .conf 以停止本地 DNS 存根侦听器。

cd /etc/systemd/
sudo cp -ip resolved.conf resolved.conf.org
sudo sed -i -e 's/#DNSStubListener=yes/DNSStubListener=no/' resolved.conf

3.    重新启动 systemd-resolved。

sudo systemctl restart systemd-resolved

---

相关信息

Amazon Route 53 DNS 的最佳实践

如何排查 Route 53 私有托管区域的 DNS 解析问题？