IP info including ISP, Usage Type, and Location provided
by IPInfo. Updated weekly.
Important Note: 51.81.164.193 is an IP address from within
our whitelist belonging to the subnet
51.81.164.192/28,
which we identify as: "Ahrefs Crawler".
Whitelisted netblocks are typically owned by trusted entities, such as Google
or Microsoft who may use them for search engine spiders. However, these same entities
sometimes also provide cloud servers and mail services which are easily abused. Pay special
attention when trusting or distrusting these IPs.
This IP address has been reported a total of
18
times from
9 distinct
sources.
51.81.164.193 was first reported on
, and the most recent report was
.
Recent Reports:
We have received reports of abusive activity from this IP address within the last week. It is
potentially still actively engaged in abusive activities.
Fail2ban automatic report for plesk-apache-badbot: 51.81.164.193 - - [15/Sep/2026:22:24:38 +0200] GE ...
show moreFail2ban automatic report for plesk-apache-badbot: 51.81.164.193 - - [15/Sep/2026:22:24:38 +0200] GET /author-sitemap.xml [DOMAIN_REMOVED] 200 6021 - Mozilla/5.0 (compatible; AhrefsBot/7.0; +[DOMAIN_REMOVED]
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(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/Un ...
show more(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/United States/proxy-us-west004-cip2.ahrefs.net)
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(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/Un ...
show more(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/United States/proxy-us-west004-cip2.ahrefs.net)
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(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/Un ...
show more(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/United States/proxy-us-west004-cip2.ahrefs.net)
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Fail2ban automatic report for plesk-apache-badbot: 51.81.164.193 - - [09/Sep/2026:13:16:08 +0200] GE ...
show moreFail2ban automatic report for plesk-apache-badbot: 51.81.164.193 - - [09/Sep/2026:13:16:08 +0200] GET /robots.txt [DOMAIN_REMOVED] 200 6280 - Mozilla/5.0 (compatible; AhrefsBot/7.0; +[DOMAIN_REMOVED]
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Fail2ban automatic report for plesk-apache-badbot: 51.81.164.193 - - [09/Sep/2026:13:16:08 +0200] GE ...
show moreFail2ban automatic report for plesk-apache-badbot: 51.81.164.193 - - [09/Sep/2026:13:16:08 +0200] GET /robots.txt [DOMAIN_REMOVED] 200 6280 - Mozilla/5.0 (compatible; AhrefsBot/7.0; +[DOMAIN_REMOVED]
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(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/Un ...
show more(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/United States/proxy-us-west004-cip2.ahrefs.net)
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(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/Un ...
show more(apache-useragents) Failed apache-useragents trigger with match [redacted] from 51.81.164.193 (US/United States/proxy-us-west004-cip2.ahrefs.net)
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Blocked abusive HTTP application-layer DoS / botnet traffic from 51.81.164.193: traffic from this ad ...
show moreBlocked abusive HTTP application-layer DoS / botnet traffic from 51.81.164.193: traffic from this address continues high-cost dynamic page and feed requests at abusive rates via TCP/HTTPS despite edge block responses. Likely compromised end-user host.
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Blocked abusive HTTP application-layer DoS / botnet traffic from 51.81.164.193: traffic from this ad ...
show moreBlocked abusive HTTP application-layer DoS / botnet traffic from 51.81.164.193: traffic from this address continues high-cost dynamic page and feed requests at abusive rates via TCP/HTTPS despite edge block responses. Likely compromised end-user host.
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Blocked abusive HTTP application-layer DoS / botnet traffic from 51.81.164.193: traffic from this ad ...
show moreBlocked abusive HTTP application-layer DoS / botnet traffic from 51.81.164.193: traffic from this address continues high-cost dynamic page and feed requests at abusive rates via TCP/HTTPS despite edge block responses. Likely compromised end-user host.
show less