---

n.razhev@n-razhev ~ % sudo /usr/sbin/sysctl -w net.inet.tcp.tso=0 && (
  for tb_sample in 1 2 3; do
    sleep 10
    date -u
    netstat -an -p tcp | awk '/194[.]186[.]63[.]/ && /ESTABLISHED/ {print}'
  done

  dig @172.21.0.1 jss.corp.mail.ru A +time=5 +tries=1 +notcp +ignore +noall +comments +answer
  dig +tcp @172.21.0.1 jss.corp.mail.ru A +time=5 +tries=1 +noall +comments +answer

  /usr/bin/curl -q -4 --noproxy '*' \
    --connect-timeout 8 --max-time 15 -sS -o /dev/null \
    -w 'JSS ip=%{remote_ip} dns=%{time_namelookup} tcp=%{time_connect} tls=%{time_appconnect} http=%{http_code} total=%{time_total}\n' \
    'https://jss.corp.mail.ru:8443/'
)
Password:
net.inet.tcp.tso: 1 -> 0
Tue Oct  6 13:05:28 UTC 2026
tcp4       0 103848  192.168.77.2.58842     194.186.63.21.443      ESTABLISHED
Tue Oct  6 13:05:38 UTC 2026
tcp4       0  43704  192.168.77.2.58842     194.186.63.21.443      ESTABLISHED
Tue Oct  6 13:05:48 UTC 2026
tcp4       0  25324  192.168.77.2.58842     194.186.63.21.443      ESTABLISHED

; <<>> DiG 9.10.6 <<>> @172.21.0.1 jss.corp.mail.ru A +time=5 +tries=1 +notcp +ignore +noall +comments +answer
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41047
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 5

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; ANSWER SECTION:
jss.corp.mail.ru.	3600	IN	A	10.12.165.142


; <<>> DiG 9.10.6 <<>> +tcp @172.21.0.1 jss.corp.mail.ru A +time=5 +tries=1 +noall +comments +answer
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 37187
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 5

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; ANSWER SECTION:
jss.corp.mail.ru.	3600	IN	A	10.12.165.142

curl: (92) HTTP/2 stream 1 was not closed cleanly: ENHANCE_YOUR_CALM (err 11)
JSS ip=10.12.165.142 dns=0.003334 tcp=1.180819 tls=2.662169 http=000 total=4.335787