$ rootlesskit --net=vpnkit dig -t srv _imaps._tcp.gmail.com
WARN[0000] specifying --disable-host-loopback is highly recommended to prohibit connecting to 127.0.0.1:* on the host namespace (requires slirp4netns or VPNKit) 
WARN[0000] Mounting /etc/resolv.conf without copying-up /etc. Note that /etc/resolv.conf in the namespace will be unmounted when it is recreated on the host. Unless /etc/resolv.conf is statically configured, copying-up /etc is highly recommended. Please refer to RootlessKit documentation for further information. 

; <<>> DiG 9.16.1-Ubuntu <<>> -t srv _imaps._tcp.gmail.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 870
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;_imaps._tcp.gmail.com.         IN      SRV

;; Query time: 0 msec
;; SERVER: 192.168.65.1#53(192.168.65.1)
;; WHEN: Mon Aug 31 20:02:57 JST 2020
;; MSG SIZE  rcvd: 39

$ ./rootlesskit --net=slirp4netns dig -t srv _imaps._tcp.gmail.com
WARN[0000] specifying --disable-host-loopback is highly recommended to prohibit connecting to 127.0.0.1:* on the host namespace (requires slirp4netns or VPNKit) 
WARN[0000] Mounting /etc/resolv.conf without copying-up /etc. Note that /etc/resolv.conf in the namespace will be unmounted when it is recreated on the host. Unless /etc/resolv.conf is statically configured, copying-up /etc is highly recommended. Please refer to RootlessKit documentation for further information. 

; <<>> DiG 9.16.1-Ubuntu <<>> -t srv _imaps._tcp.gmail.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34903
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;_imaps._tcp.gmail.com.         IN      SRV

;; ANSWER SECTION:
_imaps._tcp.gmail.com.  5       IN      SRV     5 0 993 imap.gmail.com.

;; Query time: 15 msec
;; SERVER: 10.0.2.3#53(10.0.2.3)
;; WHEN: Mon Aug 31 20:04:05 JST 2020
;; MSG SIZE  rcvd: 84