使用squidclient mgr:ipcache命令查看Squid的DNS缓存记录
如果squid端口不是3128, 需要指定端口号, squidclient -p {port} mgr:ipcache

# squidclient mgr:ipcache
...
IP Cache Statistics:
...
IP Cache Contents:Hostname                        Flg lstref    TTL  N(b)www.trendmicro.com                      19     41  1( 0)                                 23.195.109.63-OKlocalhost6.localdomain6          H      93     -1  1( 0)                                           ::1-OKlocalhost6                       H      93     -1  1( 0)                                           ::1-OKlocalhost.localdomain            H      93     -1  1( 0)                                           ::1-OKlocalhost                        H      93     -1  1( 0)                                           ::1-OKlocalhost4.localdomain4          H      93     -1  1( 0)                                     127.0.0.1-OKlocalhost4                       H      93     -1  1( 0)                                     127.0.0.1-OKwww.baidu.com                         1139  -1079  2( 0)                                103.235.47.188-OK103.235.46.96-OK

抓包

tcpdump udp port 53 -w dns.pcap 
curl -x 127.0.0.1:3128 https://www.baidu.com

参考

https://wiki.squid-cache.org/Features/CacheManager/IpCache