Must be a valid IPv4 or IPv6 ip address, e.g. 127.0.0.1 or 2001:DB8:0:0:8:800:200C:417A
Basic Info

City: unknown

Region: unknown

Country: None

Internet Service Provider: unknown

Hostname: unknown

Organization: unknown

Usage Type: unknown

Comments:
No discussion about this IP yet. Click above link to make one.
Comments on same subnet:
No discussion about this subnet yet..
Whois info:
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Dig info:
; <<>> DiG 9.10.3-P4-Ubuntu <<>> 104.21.16.21
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 44784
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;104.21.16.21.			IN	A

;; AUTHORITY SECTION:
.			230	IN	SOA	a.root-servers.net. nstld.verisign-grs.com. 2022022000 1800 900 604800 86400

;; Query time: 24 msec
;; SERVER: 183.60.83.19#53(183.60.83.19)
;; WHEN: Sun Feb 20 19:29:38 CST 2022
;; MSG SIZE  rcvd: 105
Host info
Host 21.16.21.104.in-addr.arpa. not found: 3(NXDOMAIN)
Nslookup info:
Server:		183.60.83.19
Address:	183.60.83.19#53

** server can't find 21.16.21.104.in-addr.arpa: NXDOMAIN
Related IP info:
Related comments:
IP Type Details Datetime
128.199.123.170 attack
2020-08-07T19:20:29.905184centos sshd[14850]: Failed password for root from 128.199.123.170 port 34818 ssh2
2020-08-07T19:24:46.517439centos sshd[15068]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=128.199.123.170  user=root
2020-08-07T19:24:47.985351centos sshd[15068]: Failed password for root from 128.199.123.170 port 43436 ssh2
...
2020-08-08 03:51:22
141.98.10.198 attackbots
Aug  7 14:52:27 plusreed sshd[12941]: Invalid user Administrator from 141.98.10.198
...
2020-08-08 03:55:33
141.98.10.200 attack
Aug  7 14:52:41 plusreed sshd[13017]: Invalid user admin from 141.98.10.200
...
2020-08-08 03:46:48
62.80.253.164 attack
Aug  7 15:00:20 mertcangokgoz-v4-main kernel: [418555.310623] [UFW BLOCK] IN=eth0 OUT= MAC=96:00:00:5a:6b:04:d2:74:7f:6e:37:e3:08:00 SRC=62.80.253.164 DST=94.130.96.165 LEN=52 TOS=0x00 PREC=0x00 TTL=54 ID=16333 DF PROTO=TCP SPT=3994 DPT=3000 WINDOW=64240 RES=0x00 SYN URGP=0
2020-08-08 03:52:17
122.117.106.179 attack
Unauthorized connection attempt detected from IP address 122.117.106.179 to port 23
2020-08-08 03:51:53
119.165.150.58 attack
 TCP (SYN) 119.165.150.58:43781 -> port 23, len 44
2020-08-08 03:40:02
104.223.197.227 attackspam
SSH Brute Force
2020-08-08 03:57:38
34.66.101.36 attack
Repeated brute force against a port
2020-08-08 03:22:47
31.23.211.0 attackspam
Unauthorized connection attempt from IP address 31.23.211.0 on Port 445(SMB)
2020-08-08 03:43:48
77.247.109.20 attackspam
Aug  7 21:00:43 vps339862 kernel: \[974206.930614\] \[iptables\] PORT DENIED: IN=eth0 OUT= MAC=fa:16:3e:65:a1:f6:32:a5:5e:0d:2c:d7:08:00 SRC=77.247.109.20 DST=51.254.206.43 LEN=442 TOS=0x00 PREC=0x00 TTL=54 ID=551 DF PROTO=UDP SPT=5064 DPT=5061 LEN=422 
Aug  7 21:00:43 vps339862 kernel: \[974206.930651\] \[iptables\] PORT DENIED: IN=eth0 OUT= MAC=fa:16:3e:65:a1:f6:32:a5:5e:0d:2c:d7:08:00 SRC=77.247.109.20 DST=51.254.206.43 LEN=442 TOS=0x00 PREC=0x00 TTL=54 ID=553 DF PROTO=UDP SPT=5064 DPT=5063 LEN=422 
Aug  7 21:00:43 vps339862 kernel: \[974206.930665\] \[iptables\] PORT DENIED: IN=eth0 OUT= MAC=fa:16:3e:65:a1:f6:32:a5:5e:0d:2c:d7:08:00 SRC=77.247.109.20 DST=51.254.206.43 LEN=442 TOS=0x00 PREC=0x00 TTL=54 ID=552 DF PROTO=UDP SPT=5064 DPT=5062 LEN=422 
Aug  7 21:00:43 vps339862 kernel: \[974206.930729\] \[iptables\] PORT DENIED: IN=eth0 OUT= MAC=fa:16:3e:65:a1:f6:32:a5:5e:0d:2c:d7:08:00 SRC=77.247.109.20 DST=51.254.206.43 LEN=440 TOS=0x00 PREC=0x00 TTL=54 ID=554 DF PROTO=UDP SPT=5064 DP
...
2020-08-08 03:52:28
190.242.46.250 attackspam
Unauthorized connection attempt from IP address 190.242.46.250 on Port 445(SMB)
2020-08-08 03:28:16
193.112.57.224 attackbots
SSH Brute Force
2020-08-08 03:56:59
79.133.92.34 attack
Unauthorized connection attempt from IP address 79.133.92.34 on Port 445(SMB)
2020-08-08 03:22:07
106.75.35.150 attackbots
Aug  7 12:54:14 Tower sshd[30869]: Connection from 106.75.35.150 port 56630 on 192.168.10.220 port 22 rdomain ""
Aug  7 12:54:18 Tower sshd[30869]: Failed password for root from 106.75.35.150 port 56630 ssh2
Aug  7 12:54:18 Tower sshd[30869]: Received disconnect from 106.75.35.150 port 56630:11: Bye Bye [preauth]
Aug  7 12:54:18 Tower sshd[30869]: Disconnected from authenticating user root 106.75.35.150 port 56630 [preauth]
2020-08-08 03:33:15
103.233.5.24 attackspambots
2020-08-07T19:28:37.349697amanda2.illicoweb.com sshd\[49086\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=103.233.5.24  user=root
2020-08-07T19:28:39.198473amanda2.illicoweb.com sshd\[49086\]: Failed password for root from 103.233.5.24 port 20132 ssh2
2020-08-07T19:31:11.496391amanda2.illicoweb.com sshd\[615\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=103.233.5.24  user=root
2020-08-07T19:31:13.817386amanda2.illicoweb.com sshd\[615\]: Failed password for root from 103.233.5.24 port 48516 ssh2
2020-08-07T19:33:35.647245amanda2.illicoweb.com sshd\[1099\]: pam_unix\(sshd:auth\): authentication failure\; logname= uid=0 euid=0 tty=ssh ruser= rhost=103.233.5.24  user=root
...
2020-08-08 03:24:10

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