How can I block bad bots from accessing my wiki?

Problem

Your site is sometimes overloaded with too many requests. Upon inspection you can see that most of the requests are coming from bots that may be scanning your site or crawling it for content at a rate that your wiki cannot keep up with.

Context

You are running Foswiki in Apache.

Solution

This is a very simplistic trick; bad bots and scanners can simply spoof their UA string and completely bypass these rules. A more complete solution is to use fail2ban

Block known "bad bots" detected by the user agent string using perishablepress formula (this is not the original, but modified to work in my environment):

You will need to replace 123.123.123.123 with the IP of your server; and wiki.company.org with your wiki's hostname

#2010 User-Agent Blacklist
#@ http://perishablepress.com/press/2010/08/09/2010-user-agent-blacklist/

RewriteCond %{IS_SUBREQ} ^false$
RewriteCond %{HTTP_HOST} !^(127\.0\.0\.0|localhost|123\.123\.123\.123|wiki\.company\.org)
RewriteCond %{REMOTE_HOST} !^(127\.0\.0\.0|localhost|123\.123\.123\.123|wiki\.company\.org)
RewriteCond %{HTTP_USER_AGENT} .*(Firs|exac|Cloak|Detect|uchoo|beaut|ASPSeek|swish|ICS\)|MSIE\ 6\.0\;\ Windows\ NT\;\ DigExt\)|pt\-BR\;\ rv\:1\.9\.0\.3\)\ Firefox\/3\.0|pt\-BR\;\ rv\:1\.9\.0\.18\)\ Firefox\/3\.0|\!susie|\$x0e|\%0a|\%0d|\@\$x|\_irc|\_works|\+select\+|\+union\+|\<\?|1\,\1\,1\,|3gse|4all|4anything|5\.1\;\ xv6875\)|59\.64\.153\.|85\.17\.|88\.0\.106\.|98|a\_browser|a1\ site|abac|abach|abby|aberja|abilon|abont|abot|accept|access|accoo|accoon|aceftp|acme|active|address|adopt|adress|advisor|agent|ahead|aihit|aipbot|alarm|albert|alek|alexa\ toolbar\;\ \(r1\ 1\.5\)|alltop|alma|alot|alpha|america\ online\ browser\ 1\.1|amfi|amfibi|anal|andit|anon|ansearch|answer|answerbus|answerchase|antivirx|apollo|appie|arach|archive|arian|aboutoil|asps|aster|atari|atlocal|atom|atrax|atrop|attrib|autoh|autohot|av\ fetch|avsearch|axod|axon|baboom|baby|back|baid|bali|bandit|barry|basichttp|batch|bdfetch|beat|become|bee|beij|betabot|biglotron|bilgi|bison|bitacle|bitly|blaiz|blitz|blogl|blogscope|blogzice|bloob|blow|bord|boi|bond|boris|bost|bot\.ara|botje|botw|bpimage|brand|brok|broth|browseabit|browsex|bruin|bsalsa|bsdseek|built|bulls|bumble|bunny|busca|busi|buy|bwh3|cafek|cafi|camel|cand|captu|casper|catch|ccbot|ccubee|cd34|ceg|cfnetwork|cgichk|cha0s|chang|chaos|char|char\(|chase\ x|check\_http|checker|checkonly|chek|chill|chttpclient|cipinet|cisco|cita|citeseer|clam|claria|claw|clush|coast|code\.com|cogent|coldfusion|coll|collect|comb|combine|commentreader|common|compan|compatible\-|conc|conduc|contact|control|contype|conv|cool|copi|copy|coral|corn|cosmos|costa|cowbot|cr4nk|craft|cralwer|crank|crap|crawler0|crazy|cres|cs\-cz|cshttp|cuill|CURI|curl|curry|custo|cute|cyber|cz3|czx|daily|dalvik|daobot|dark|darwin|data|daten|dcbot|dcs|dds\ explorer|deep|deps|detect|dex|diam|diibot|dillo|ding|disc|disp|ditto|dlc|doco|dotbot|drag|drec|dsdl|dsok|dts|duck|dumb|eag|earn|earthcom|easydl|ebin|echo|edco|egoto|elnsb5|email|emer|empas|encyclo|enfi|enhan|enterprise\_search|envolk|erck|erocr|eventax|evere|evil|ewh|exploit|expre|extra|eyen|fang|fast|fastbug|faxo|fdse|feed24|feeddisc|feedhub|fetch|filan|fileboo|fimap|find|firebat|firedownload\/1\.2pre\ firefox\/3\.6|firefox\/0|firefox\/1|firefox\/2|firs|flam|flash|flexum|flip|fly|focus|fooky|forum|forv|fost|foto|foun|fount|foxy\/1\;|free|friend|frontpage|fuck|fuer|futile|fyber|gais|galbot|gbpl|gecko\/2001|gecko\/2002|gecko\/2006|gecko\/2009042316|gener|geni|geo|geona|geth|getr|getw|ggl|gira|gluc|gnome|go\!zilla|goforit|goldfire|gonzo|google\ wireless|googlebot\-image|gosearch|got\-it|gozilla|grab|graf|greg|grub|grup|gsa\-cra|gsearch|gt\:\:www|guidebot|guruji|gyps|haha|hailo|harv|hash|hatena|hax|head|helm|herit|heritrix|hgre|hippo|hloader|hmse|hmview|holm|holy|hotbar\ 4\.4\.5\.0|hpprint|httpclient|httpconnect|httplib|human|huron|hverify|hybrid|hyper|iaskspi|ibm\ evv|iccra|ichiro|icopy|ida|ie\/5\.0|ieauto|iempt|iexplore\.exe|ilium|ilse|iltrov|indexer|indy|ineturl|infonav|innerpr|inspect|insuran|intellig|interget|internet\_explorer|internet\x|intraf|ip2|ipsel|irlbot|isc\_sys|isilo|isrccrawler|isspi|jady|jaka|jam|jenn|jet|jiro|jobo|joc|jupit|just|jyx|jyxo|kash|kazo|kbee|kenjin|kernel|keywo|kfsw|kkma|kmc|know|kosmix|krae|krug|ksibot|ktxn|kum|labs|lanshan|lapo|larbin|leech|lets|lexi|lexxe|libby|libcrawl|libcurl|libfetch|libweb|libwww|light|linc|lingue|linkcheck|linklint|linkman|lint|list|litefeeds|livedoor|livejournal|liveup|lmq|locu|london|lone|loop|lork|lth\_|lwp|mac\_f|magi|magp|mail\.ru|main|majest|mam|mama|mana|marketwire|masc|mass|mata|mvi|mcbot|mecha|mechanize|mediapartners|metadata|metalogger|metaspin|metauri|mete|mib\/2\.2|microsoft\.url|microsoft\_internet\_explorer|mido|miggi|miix|mindjet|mindman|mips|mira|mire|miss|mist|mizz|mj12|mlbot|mlm|mnog|moge|moje|mooz|more|mouse|mozdex) [NC]
RewriteRule ^.*$ - [G]

RewriteCond %{IS_SUBREQ} ^false$
RewriteCond %{HTTP_HOST} !^(127\.0\.0\.0|localhost|123\.123\.123\.123|wiki\.company\.org)
RewriteCond %{REMOTE_HOST} !^(127\.0\.0\.0|localhost|123\.123\.123\.123|wiki\.company\.org)
RewriteCond %{HTTP_USER_AGENT} .*(Windows\ NT\ 6\.1\;\ tr\;\ rv\:1\.9\.2\.6\)|mozilla\/0|mozilla\/1|mozilla\/2|mozilla\/3|mozilla\/4\.61\ \[en\]|mozilla\/firefox|mpf|msie\ 1|msie\ 2|msie\ 3|msie\ 4|msie\ 5|msie\ 6\.0\-|msie\ 6\.0b|msie\ 7\.0a1\;|msie\ 7\.0b\;|msie6xpv1|msiecrawler|msnbot\-media|msnbot\-products|msnptc|msproxy|msrbot|musc|mvac|mwm|my\_age|myapp|mydog|myeng|myie2|mysearch|myurl|nag|name|naver|navr|near|netants|netcach|netcrawl|netfront|netinfo|netmech|netsp|netx|netz|neural|neut|newsbreak|newsgatorinbox|newsrob|newt|next|ng\-s|ng\/2|nice|nikto|nimb|ninja|ninte|nog|noko|nomad|norb|note|npbot|nuse|nutch|nutex|nwsp|obje|ocel|octo|odi3|oegp|offby|offline|omea|omg|omhttp|onfo|onyx|openf|openssl|openu|opera\ 2|opera\ 3|opera\ 4|opera\ 5|opera\ 6|opera\ 7|orac|orbit|oreg|osis|our|outf|owl|p3p\_|page2rss|pagefet|pansci|parser|patw|pavu|pb2pb|pcbrow|pear|peer|pepe|perfect|perl|petit|phoenix\/0\.|php|phras|picalo|piff|pig|pingd|pipe|pirs|plag|planet|plant|platform|playstation|plesk|pluck|plukkie|poe\-com|poirot|pomp|post|postrank|powerset|preload|press|privoxy|probe|program\_shareware|protect|protocol|prowl|proxie|proxy|psbot|pubsub|puf|pulse|punit|purebot|purity|pyq|pyth|query|quest|qweer|radian|rambler|ramp|rapid|rawdog|rawgrunt|reap|reeder|refresh|reget|relevare|repo|requ|request|rese|retrieve|rip|rix|rma|roboz|rocket|rogue|rpt\-http|rsscache|ruby|ruff|rufus|rv\:0\.9\.7\)|salt|sample|sauger|savvy|sbcyds|sbider|sblog|sbp|scagent|scanner|scej\_|sched|schizo|schlong|schmo|scorp|scott|scout|scrawl|screen|screenshot|script|seamonkey\/1\.5a|search17|searchbot|searchme|sega|semto|sensis|seop|seopro|sept|sezn|seznam|share|sharp|shaz|shell|shelo|sherl|shim|shopwiki|silurian|simple|simplepie|siph|sitekiosk|sitescan|sitevigil|sitex|skam|skimp|sledink|sleip|slide|sly|smag|smurf|snag|snapbot|snapshot|snif|snip|snoop|sock|socsci|sogou|sohu|solr|some|soso|spad|span|spbot|speed|sphere|spin|sproose|spurl|sputnik|spyder|squi|sqwid|sqworm|ssm\_ag|stack|stamp|statbot|state|steel|stilo|strateg|stress|strip|style|subot|such|suck|sume|sunos\ 5\.7|sunrise|superbot|superbro|supervi|surf4me|surfbot|survey|susi|suza|suzu|sweep|sygol|synapse|sync2it|systems|szukacz|tagger|tagoo|tagyu|take|talkro|tamu|tandem|tarantula|tbot|tcf|tcs\/1|teamsoft|tecomi|teesoft|teleport|telesoft|tencent|terrawiz|test|texnut|thomas|tiehttp|timebot|timely|tipp|tiscali|titan|tmcrawler|tmhtload|tocrawl|todobr|tongco|toolbar\;\ \(r1|topic|topyx|torrent|track|translate|traveler|treeview|tricus|trivia|trivial|true|tunnel|turing|turnitin|tutorgig|twat|tweak|twice|tygo|ubee|ultraseek|unavail|unf|universal|unknown|upg1|uptime|urlbase|urllib|urly|user\-agent\:|useragent|usyd|vagabo|valet|vamp|vci|veri\~li|verif|versus|via|virtual|visual|void|voyager|vsyn|w0000t|w3search|walhello|walker|wand|waol|watch|wavefire|wbdbot|weather|web\.ima|web2mal|webarchive|webbot|webcat|webcor|webcorp|webcrawl|webdat|webdup|webgo|webind|webis|webitpr|weblea|webmin|webmoney|webp|webql|webrobot|webster|websurf|webtre|webvac|webzip|wells|wep\_s|wget|whiz|widow|win67|windows\-rss|windows\ 2000|windows\ 3|windows\ 95|windows\ 98|windows\ ce|windows\ me|winht|winodws|wish|wizz|wordp|worio|works|world|worth|wwwc|wwwo|wwwster|xaldon|xbot|xenu|xirq|y\!tunnel|yacy|yahoo\-mmaudvid|yahooseeker|yahooysmcm|yamm|yand|yandex|yang|yoono|yori|yotta|yplus\ |ytunnel|zade|zagre|zeal|zebot|zerx|zeus|zhuaxia|zipcode|zixy|zmao) [NC]
RewriteRule ^.*$ - [G]

Known Limitations

This can sometimes block legitimate non-human users (google and friends should be unaffected), such as ./build.pl upload or other simple scripts you've devised to work on your wiki from the web.

See Also

BlackListPlugin

-- PaulHarvey - 10 Nov 2010