CloudFlare provides web performance and security solutions, enhancing site speed and protecting against threats.
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cf_use_ob
The cf_use_ob cookie informs Cloudflare to fetch the requested resource from the Always Online cache on the designated port. Applicable values are: 0, 80, and 443. The cf_ob_info and cf_use_ob cookies are persistent cookies that expire after 30 seconds.
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__cfwaitingroom
The __cfwaitingroom cookie is only used to track visitors that access a waiting room enabled host and path combination for a zone. Visitors using a browser that does not accept cookies cannot visit the host and path combination while the waiting room is active.
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cf_chl_rc_i
These cookies are for internal use which allows Cloudflare to identify production issues on clients.
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cf_chl_rc_ni
These cookies are for internal use which allows Cloudflare to identify production issues on clients.
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cf_chl_rc_m
These cookies are for internal use which allows Cloudflare to identify production issues on clients.
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__cfruid
Used by the content network, Cloudflare, to identify trusted web traffic.
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__cf_bm
Cloudflare's bot products identify and mitigate automated traffic to protect your site from bad bots. Cloudflare places the __cf_bm cookie on End User devices that access Customer sites that are protected by Bot Management or Bot Fight Mode. The __cf_bm cookie is necessary for the proper functioning of these bot solutions.
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__cflb
When enabling session affinity with Cloudflare Load Balancer, Cloudflare sets a __cflb cookie with a unique value on the first response to the requesting client. Cloudflare routes future requests to the same origin, optimizing network resource usage. In the event of a failover, Cloudflare sets a new __cflb cookie to direct future requests to the failover pool.
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_cfuvid
The _cfuvid cookie is only set when a site uses this option in a Rate Limiting Rule, and is only used to allow the Cloudflare WAF to distinguish individual users who share the same IP address.
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cf_clearance
Whether a CAPTCHA or Javascript challenge has been solved.
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__cfseq
Sequence rules uses cookies to track the order of requests a user has made and the time between requests and makes them available via Cloudflare Rules. This allows you to write rules that match valid or invalid sequences. The specific cookies used to validate sequences are called sequence cookies.
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cf_ob_info
The cf_ob_info cookie provides information on: The HTTP Status Code returned by the origin web server. The Ray ID of the original failed request. The data center serving the traffic
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Praveen Kumar 
1 comment
Love the last stanza!