为什么我看不到特定域的 CNAME 记录？答案

【问题标题】：Why I can't see the CNAME record of a specific domain?为什么我看不到特定域的 CNAME 记录？
【发布时间】：2021-09-22 16:09:18
【问题描述】：

为什么当我想查看哪个 CNAMES 具有特定域时，我无法使用 dig/nslookup 查看它们？ nslookup -type=any google.com

CNAMES 是否受到保护以防止公众请愿？命令输出：

;; Truncated, retrying in TCP mode.
Server:     8.8.4.4
Address:    8.8.4.4#53

Non-authoritative answer:
Name:   google.com
Address: 142.250.185.206
google.com  has AAAA address 2a00:1450:4001:812::200e
google.com  mail exchanger = 20 alt1.aspmx.l.google.com.
google.com  text = "google-site-verification=wD8N7i1JTNTkezJ49swvWW48f8_9xveREV4oB-0Hf5o"
google.com  nameserver = ns2.google.com.
google.com  mail exchanger = 10 aspmx.l.google.com.
google.com  nameserver = ns3.google.com.
google.com  text = "MS=E4A68B9AB2BB9670BCE15412F62916164C0B20BB"
google.com  rdata_257 = 0 issue "pki.goog"
google.com  text = "globalsign-smime-dv=CDYX+XFHUw2wml6/Gb8+59BsH31KzUr6c1l2BPvqKX8="
google.com  nameserver = ns1.google.com.
google.com  text = "facebook-domain-verification=22rm551cu4k0ab0bxsw536tlds4h95"
google.com  mail exchanger = 30 alt2.aspmx.l.google.com.
google.com  text = "v=spf1 include:_spf.google.com ~all"
google.com  text = "apple-domain-verification=30afIBcvSuDV2PLX"
google.com  text = "docusign=05958488-4752-4ef2-95eb-aa7ba8a3bd0e"
google.com  mail exchanger = 50 alt4.aspmx.l.google.com.
google.com  text = "google-site-verification=TV9-DBe4R80X4v0M4U_bd_J9cpOJM0nikft0jAgjmsQ"
google.com  nameserver = ns4.google.com.
google.com  mail exchanger = 40 alt3.aspmx.l.google.com.
google.com
    origin = ns1.google.com
    mail addr = dns-admin.google.com
    serial = 384422044
    refresh = 900
    retry = 900
    expire = 1800
    minimum = 60
google.com  text = "docusign=1b0a6754-49b1-4db5-8540-d2c12664b289"

Authoritative answers can be found from:

【问题讨论】：

标签： cname nslookup dig

【解决方案1】：

CNAME 记录是公开的，您应该可以看到它们。如果您没有看到它们，则很可能是该域根本没有 CNAME 记录。

尝试几个不同的域，尤其是子域，因为它们通常包含 CNAME 记录。例如

~ → nslookup -type=CNAME www.pinterest.com

Server:     2001:558:feed::1
Address:    2001:558:feed::1#53

Non-authoritative answer:
www.pinterest.com   canonical name = www-pinterest-com.gslb.pinterest.com.

Authoritative answers can be found from:

【讨论】：