dig 命令异常

环境是 VMware 虚拟机装的 Linux Mint ，在 VMware 软件的 NAT 网络模式里面设置了 DNS： 10.x 的公司内网 DNS 两个公开 DNS 223.5.5.5 8.8.8.8

为啥要在 VMware 里面设置 DNS 是由于出差在外面用 4G 连公司 VPN 的时候，老是解析不了公司内网的 API 接口，于是把公司内网 DNS 直接设置到了 VMWare 的 NAT 模式下的 DNS 配置中。

然后我回到公司接入网线，发现 dig 不好使了，nslookup 倒是没有问题。

 nslookup
> www.baidu.com
Server:		127.0.0.53
Address:	127.0.0.53#53

Non-authoritative answer:
www.baidu.com	canonical name = www.a.shifen.com.
Name:	www.a.shifen.com
Address: 220.181.38.150
Name:	www.a.shifen.com
Address: 220.181.38.149

dig 的话，指定 dns 服务器均提示 connection timed out

# mint @ mint-virtual-machine in ~ [14:30:23] C:9
$ ping 114.114.114.114
PING 114.114.114.114 (114.114.114.114) 56(84) bytes of data.
64 bytes from 114.114.114.114: icmp_seq=1 ttl=128 time=20.8 ms
64 bytes from 114.114.114.114: icmp_seq=2 ttl=128 time=21.7 ms
^C
--- 114.114.114.114 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 20.898/21.313/21.728/0.415 ms
(base) 
# mint @ mint-virtual-machine in ~ [14:41:22] 
$ dig @114.114.114.114 www.baidu.com 


; <<>> DiG 9.11.3-1ubuntu1.15-Ubuntu <<>> @114.114.114.114 www.baidu.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
(base) 
# mint @ mint-virtual-machine in ~ [14:41:48] C:9
$ dig @114.114.114.114 +notrace www.baidu.com


; <<>> DiG 9.11.3-1ubuntu1.15-Ubuntu <<>> @114.114.114.114 +notrace www.baidu.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached

不指定的话显示是从 127.0.0.53 获取的解析记录，但是不指定的情况下+trace 参数失效。

(base) 
# mint @ mint-virtual-machine in ~ [14:42:38] C:9
$ dig  www.baidu.com 


; <<>> DiG 9.11.3-1ubuntu1.15-Ubuntu <<>> www.baidu.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6883
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;www.baidu.com.			IN	A

;; ANSWER SECTION:
www.baidu.com.		5	IN	CNAME	www.a.shifen.com.
www.a.shifen.com.	4	IN	A	220.181.38.150
www.a.shifen.com.	4	IN	A	220.181.38.149

;; Query time: 331 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Thu Jan 20 14:42:53 CST 2022
;; MSG SIZE  rcvd: 101

(base) 
# mint @ mint-virtual-machine in ~ [14:42:53] 
$ dig +trace www.baidu.com


; <<>> DiG 9.11.3-1ubuntu1.15-Ubuntu <<>> +trace www.baidu.com
;; global options: +cmd
;; Received 51 bytes from 127.0.0.53#53(127.0.0.53) in 0 ms