Apr 26 18:22:14 srv01 sshd[28004]: Invalid user kai from 5.3.87.8 port 36474
Apr 26 18:22:14 srv01 sshd[28004]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=5.3.87.8
Apr 26 18:22:14 srv01 sshd[28004]: Invalid user kai from 5.3.87.8 port 36474
Apr 26 18:22:16 srv01 sshd[28004]: Failed password for invalid user kai from 5.3.87.8 port 36474 ssh2
Apr 26 18:26:26 srv01 sshd[28182]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=5.3.87.8  user=root
Apr 26 18:26:29 srv01 sshd[28182]: Failed password for root from 5.3.87.8 port 47950 ssh2
...

Apr 26 13:19:25 sigma sshd\[2935\]: Invalid user hf from 51.255.168.254Apr 26 13:19:27 sigma sshd\[2935\]: Failed password for invalid user hf from 51.255.168.254 port 38690 ssh2
...

Apr 26 13:58:56 debian-2gb-nbg1-2 kernel: \[10161271.919340\] \[UFW BLOCK\] IN=eth0 OUT= MAC=96:00:00:0e:18:f4:d2:74:7f:6e:37:e3:08:00 SRC=134.122.76.227 DST=195.201.40.59 LEN=40 TOS=0x00 PREC=0x00 TTL=246 ID=31925 PROTO=TCP SPT=40320 DPT=8067 WINDOW=1024 RES=0x00 SYN URGP=0

2020-04-26T20:25:03.132745abusebot-5.cloudsearch.cf sshd[28422]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=49.212.43.150  user=root
2020-04-26T20:25:05.087858abusebot-5.cloudsearch.cf sshd[28422]: Failed password for root from 49.212.43.150 port 56240 ssh2
2020-04-26T20:27:13.545525abusebot-5.cloudsearch.cf sshd[28469]: Invalid user murphy from 49.212.43.150 port 42514
2020-04-26T20:27:13.553438abusebot-5.cloudsearch.cf sshd[28469]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=49.212.43.150
2020-04-26T20:27:13.545525abusebot-5.cloudsearch.cf sshd[28469]: Invalid user murphy from 49.212.43.150 port 42514
2020-04-26T20:27:15.689089abusebot-5.cloudsearch.cf sshd[28469]: Failed password for invalid user murphy from 49.212.43.150 port 42514 ssh2
2020-04-26T20:29:21.963585abusebot-5.cloudsearch.cf sshd[28474]: Invalid user murphy from 49.212.43.150 port 57019
...

$f2bV_matches

Apr 26 13:58:33 debian-2gb-nbg1-2 kernel: \[10161249.278369\] \[UFW BLOCK\] IN=eth0 OUT= MAC=96:00:00:0e:18:f4:d2:74:7f:6e:37:e3:08:00 SRC=139.162.116.22 DST=195.201.40.59 LEN=40 TOS=0x00 PREC=0x00 TTL=241 ID=54321 PROTO=TCP SPT=33767 DPT=1755 WINDOW=65535 RES=0x00 SYN URGP=0

Apr 26 22:05:34 debian-2gb-nbg1-2 kernel: \[10190467.922327\] \[UFW BLOCK\] IN=eth0 OUT= MAC=96:00:00:0e:18:f4:d2:74:7f:6e:37:e3:08:00 SRC=134.122.86.253 DST=195.201.40.59 LEN=45 TOS=0x00 PREC=0x00 TTL=246 ID=54321 PROTO=UDP SPT=43373 DPT=53413 LEN=25

(sshd) Failed SSH login from 210.16.93.20 (IN/India/webmail.redbytes.in): 5 in the last 3600 secs

2020-04-26 22:04:14 dovecot_login authenticator failed for \(\[185.50.149.3\]\) \[185.50.149.3\]: 535 Incorrect authentication data \(set_id=info@nophost.com\)
2020-04-26 22:04:24 dovecot_login authenticator failed for \(\[185.50.149.3\]\) \[185.50.149.3\]: 535 Incorrect authentication data
2020-04-26 22:04:36 dovecot_login authenticator failed for \(\[185.50.149.3\]\) \[185.50.149.3\]: 535 Incorrect authentication data
2020-04-26 22:04:42 dovecot_login authenticator failed for \(\[185.50.149.3\]\) \[185.50.149.3\]: 535 Incorrect authentication data
2020-04-26 22:04:57 dovecot_login authenticator failed for \(\[185.50.149.3\]\) \[185.50.149.3\]: 535 Incorrect authentication data

Apr 26 19:01:23 master sshd[32396]: Failed password for invalid user pmc2 from 138.68.29.69 port 53048 ssh2

2020-04-26T18:35:47.698656abusebot-7.cloudsearch.cf sshd[15846]: Invalid user webadmin from 54.38.242.233 port 51980
2020-04-26T18:35:47.705144abusebot-7.cloudsearch.cf sshd[15846]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=233.ip-54-38-242.eu
2020-04-26T18:35:47.698656abusebot-7.cloudsearch.cf sshd[15846]: Invalid user webadmin from 54.38.242.233 port 51980
2020-04-26T18:35:49.970160abusebot-7.cloudsearch.cf sshd[15846]: Failed password for invalid user webadmin from 54.38.242.233 port 51980 ssh2
2020-04-26T18:44:13.636620abusebot-7.cloudsearch.cf sshd[16896]: Invalid user pl from 54.38.242.233 port 40102
2020-04-26T18:44:13.643832abusebot-7.cloudsearch.cf sshd[16896]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=233.ip-54-38-242.eu
2020-04-26T18:44:13.636620abusebot-7.cloudsearch.cf sshd[16896]: Invalid user pl from 54.38.242.233 port 40102
2020-04-26T18:44:15.874374abusebot-7.cloudsearch.cf sshd
...

Apr 27 01:05:16 gw1 sshd[12908]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=168.232.136.111
Apr 27 01:05:18 gw1 sshd[12908]: Failed password for invalid user newrelic from 168.232.136.111 port 38372 ssh2
...

Apr 26 22:01:19 Ubuntu-1404-trusty-64-minimal sshd\[19425\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=218.92.0.168  user=root
Apr 26 22:01:21 Ubuntu-1404-trusty-64-minimal sshd\[19425\]: Failed password for root from 218.92.0.168 port 25166 ssh2
Apr 26 22:01:40 Ubuntu-1404-trusty-64-minimal sshd\[19610\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=218.92.0.168  user=root
Apr 26 22:01:43 Ubuntu-1404-trusty-64-minimal sshd\[19610\]: Failed password for root from 218.92.0.168 port 50945 ssh2
Apr 26 22:02:38 Ubuntu-1404-trusty-64-minimal sshd\[19903\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=218.92.0.168  user=root

2020-04-26T20:58:27.696592hermes postfix/smtpd[151520]: NOQUEUE: reject: RCPT from unknown[180.107.181.53]: 554 5.7.1 Service unavailable; Client host [180.107.181.53] blocked using zen.spamhaus.org; https://www.spamhaus.org/query/ip/180.107.181.53; from= to= proto=ESMTP helo=
...

scans once in preceeding hours on the ports (in chronological order) 5986 resulting in total of 43 scans from 162.243.0.0/16 block.