Mongrel2服务器配置及控制
介绍
Mongrel2是一款面向现代Web应用（Web2.0以及以后）而设计的Web浏览器。由干净的C语言写成，（目前）在Linux（及类似的Unix）系统上运行。它支持HTTP,Flashsockets,WebSockets,LongPolling，异步等技术，基本上走在当今Web服务端技术的最前沿。
主页
http://mongrel2.org/
手册
http://mongrel2.org/static/mongrel2-manual.html
Mongrel2的理念
按前面的描述，Mongrel2听起来是个很牛X的Web服务器，其实它真正独特的地方还不是前面的描述，而是它的理念：
- Web服务框架。它提供了很多基础设施，封装了大量Web处理方面的细节，并且以消息的方式为服务器更里层的应用提供多种服务；
- 语言中立。Mongrel2本身是用C语言写成的，但是他力求做到提供的服务语言中立（包括内部协议的设计），理论上可以为任何语言使用（只要这种语言能处理字符串）。实际上，目前已经有17种语言为它写了接口模块，所以可以说到现在为止他已经实现这个目标；
- 多样灵活的控制接口，为管理员的精确控制提供了方便（甚至可以精确到控制一个持续性连接）；
关于语言中立，我们来八卦一下。Mongrel2的作者ZedShaw，之前是Ruby社区的一位大牛，为Ruby社区设计了Mongrel服务器（针对Ruby设计的），这是个广受好评的WebServer，效率差不多是Ruby社区最高的了。后来，不知道咋回事儿（可能是关于一些Ruby技术的发展观点的分歧），ZedShaw与Ruby界的其它某些人闹翻了。于是他一怒之下退出了Ruby圈子，发誓再也不搞Ruby了。退出之后，兴趣转向了python，写了一本书LearnPython:TheHardWay。2010年开始，带着对Ruby界的愤怒（也许是很受伤），他开始了Mongrel2的设计。Mongrel2与Mongrel理念完全不一样，Mongrel2的目标就是要语言中立，并且宣称未来的软件开发一定是语言无关的（这种观念我蛮赞同）。就这么一年多的时间，到现在为止（2011年8月10日），发展到了1.7.5版，影响力逐渐大了起来。
Mongrel2与ZeroMQ社区也很有渊源——Mongrel2是ZeroMQ的第一个比较正式的有影响力的项目。ZeroMQ宣称是最牛逼的消息队列，是个新东西，可一直没有什么有影响力的应用。这次与Mongrel2的联姻，简直就是天作之合，我看行！
我关注Mongrel2，还是在其Tir示意框架出来之后，那时Mongrel2的版本为1.4。当时我正在估摸着设计一款Lua的Web框架，用于我们以后的产品中。发现Tir后，立即对这一套系统进行了消化，觉得Mongrel2,ZeroMQ,Redis,Lua的配合绝对有戏，重要的是在Mongrel2的基础上开发Web框架，能省很多事情（Mongrel2把许多以许需要框架来完成的事情包装好了）。于是立马开始了Bamboo项目。
配置文件写法
对象
- Server
- Host
- Dir
- Proxy
内置变量
- settings
- servers
配置选项
先贴上，后面再翻译。
Thelistofavailablesettingsare:
control_port=ipc://run/control
ThisiswhereMongrel2willlistenwith0MQforcontrolmessages.Youshoulduseipc://forthespec,sothatonlyalocaluserwithfileaccesscangetatit.
limits.buffer_size=2*1024
InternalIObuffers,usedforthingslikeproxyingandhandlingrequests.Thisisaveryconservativesetting,soifyougetHTTPheadersgreaterthanthis,you’llwanttoincreasethissetting.You’llalsowanttoshootwhoeverissendingyouthoserequests,becausetheaverageis400-600bytes.
limits.client_read_retries=5
HowmanytimesitwillattempttoreadacompleteHTTPheaderfromaclient.Thispreventsattackswhereaclienttricklesanincompleterequestatyouuntilyourunoutofresources.
limits.connection_stack_size=32*1024
Sizeofthestackusedforconnectioncoroutines.Ifyou’retryingtocramatonofconnectionsintoverylittleRAM,seehowlowthiscango.
limits.content_length=20*1024
Maximumallowedcontentlengthonsubmittedrequests.Thisis,rightnow,ahardlimitsorequeststhatgooveritarerejected.LaterversionsofMongrel2willuseanuploadmechanismthatwillallowanysizeupload.
limits.dir_max_path=256
MaxpathlengthyoucansetforDirhandlers.
limits.dir_send_buffer=16*1024
Maximumbufferusedforfilesendingwhenweneedtouseone.
limits.fdtask_stack=100*1024
StackframesizeforthemainIOreactortask.There’sonlyone,sosetithighifyoucan,butitcouldpossiblygolower.
limits.handler_stack=100*1024
ThestackframesizeforanyHandlertasks.Youprobablywantthishigh,sincethere’snotmanyofthese,butadjustandseewhatyoursystemcanhandle.
limits.handler_targets=128
ThemaximumnumberofconnectionIDsamessagefromaHandlermaytarget.It’snotsmarttosetthisreallyhigh.
limits.header_count=128*10
Maximumnumberofallowedheadersfromaclientconnection.
limits.host_name=256
MaximumhostnameforHostspecifiersandotherDNSrelatedsettings.
limits.mime_ext_len=128
MaximumlengthofMIMEtypeextensions.
limits.proxy_read_retries=100
ThenumberofreadattemptsMongrel2shouldmakewhenreadingfromabackendproxy.Manybackendserversdon’tbuffertheirI/OproperlyandMongrel2willditchtheirHTTPresponseifitdoesn’tgetaheaderafterthismanyattempts.
limits.proxy_read_retry_warn=10
Thisisthethresholdwhereyougetawarningthataparticularbackendishavingperformanceproblems,usefulforspottingpotentialerrorsbeforetheybecomeaproblem.
limits.url_path=256
MaxURLpaths.Doesnotincludequerystring,justpath.
superpoll.hot_dividend=4
Ratioofthetotal(like1/4th,1/8th)thatshouldbeinthehotselection.Setthishigherifyouhavelotsofidleconnections;setitlowerifyouhavemoreactiveconnections.
superpoll.max_fd=10*1024
Maximumpossibleopenfiles.Donotsetthisabove64*1024,andexpectittotakeabitwhileMongrel2setsupconstantstructures.
upload.temp_store=None
Thisisnotsetbydefault.Ifyouwantlargerequeststoreachyourhandlers,thensetthistoadirectorytheycanaccess,andmakesuretheycanhandleit.ReadaboutitintheHackingsectionunderUploads.ThefilehastoendinXXXXXXcharstowork(readmanmkstemp).
upload.temp_store_mode=0666
Themodetochmodanyfilesuploadedtoupload.temp_store.
zeromq.threads=1
Numberof0MQIOthreadstorun.Careful,we’veexperiencedthreadbugsin0MQsometimeswithhighnumbersofthese.
limits.tick_timer=10
Mongrel2keepsaninternalclockforefficiencyandtorunthetimeouts.Thisishowoftenthatclockupdates,anddefaultsto10seconds.
limits.min_ping=120
Minimumtimesincelastactivitybeforeconsideringclosingasocket.Setto0todisableit.
limits.min_write_rate=300
Minimumbytes/secondwrittenbeforeconsideringclosingasocket.Setto0todisableit.
limits.min_read_rate=300
Minimumbytes/secondreadbeforeconsideringclosingasocket.Setto0todisableit.
limits.kill_limit=2
Howmanyofmin_ping,min_write_rate,andmin_read_ratehavetotriggerbeforeasocketiskilled.
m2sh管理工具
Mongrel2的源码包里面自带一个工具m2sh，可以用来方便地从命令行管理Mongrel2。
在命令行中敲入m2sh，回车。会进入下面的提示符：
==============================================
mongrel2>help
Mongrel2m2shhasthesecommandsavailable:
loadLoadaconfig.
configAliasforload.
shellStartsaninteractiveshell.
accessPrintstheaccesslog.
serversListstheserversinaconfigdatabase.
hostsListsthehostsinaserver.
routesListstheroutesinahost.
commitAddsamessagetothelog.
logPrintsthecommitlog.
startStartsaserver.
stopStopsaserver.
reloadReloadsaserver.
runningTellsyouwhat'srunning.
controlConnectstothecontrolport.
versionPrintstheMongrel2andm2shversion.
helpGethelp,listscommands.
uuidPrintsoutarandomlygeneratedUUID.
==============================================
m2shservers--dbconf/config.sqlite
SERVERS:
------
mainipaste505417b8-1de4-454f-98b6-07eb9225cca1
server2tfzhw505417b8-1de4-454f-98b6-07eb9225cca2
==============================================
mongrel2>hosts--dbconf/config.sqlite-servername
HOSTSinname:
-----
[ERROR](errno:Nosuchfileordirectory)Invalidquery,ithasnocolumns,whichisabug.
mongrel2>hosts--dbconf/config.sqlite-servermain
HOSTSinmain:
-----
1ipaste
==============================================
mongrel2>routes--dbconf/config.sqlite-servermain-hostipaste
ROUTESinhostipaste,servermain
-----
/
/media/
/favicon.ico
==============================================
mongrel2>log--dbconf/config.sqlite
LOGMESSAGES:
------
2011-01-1205:41:34rootlegerobot-officeconf/mongrel2.confloadcommand
2011-01-1806:26:54rootlegerobot-officeconf/mongrel2.confloadcommand
2011-01-1806:29:54rootlegerobot-officeconf/mongrel2.confloadcommand
2011-01-1806:46:34rootlegerobot-officeconf/mongrel2.confloadcommand
2011-01-1806:47:15rootlegerobot-officeconf/mongrel2.confloadcommand
2011-01-1806:51:39rootlegerobot-officeconf/mongrel2.confloadcommand
2011-01-2707:47:56rootlegerobot-officeconf/mongrel2.confloadcommand
==============================================
mongrel2>access--dbconf/config.sqlite
[WARN](errno:Nosuchfileordirectory)Nooption--loggiven,using"logs/access.log"asthedefault.
[1312945845]192.168.0.101:2633ipaste"GET/get/HTTP/1.1"2000
[1312945874]192.168.0.101:2634ipaste"GET/HTTP/1.1"2000
[1312945874]192.168.0.101:2634ipaste"GET/media/js/jquery.min.jsHTTP/1.1"3040
[1312945874]192.168.0.101:2635ipaste"GET/media/css/fileuploader.cssHTTP/1.1"3040
[1312945874]192.168.0.101:2636ipaste"GET/media/js/fileuploader.jsHTTP/1.1"3040
[1312945874]192.168.0.101:2637ipaste"GET/get/HTTP/1.1"2000
[1312945875]192.168.0.101:2639ipaste"GET/HTTP/1.1"2000
[1312945875]192.168.0.101:2639ipaste"GET/media/js/jquery.min.jsHTTP/1.1"3040
[1312945875]192.168.0.101:2640ipaste"GET/media/css/fileuploader.cssHTTP/1.1"3040
[1312945875]192.168.0.101:2641ipaste"GET/media/js/fileuploader.jsHTTP/1.1"3040
[1312945875]192.168.0.101:2642ipaste"GET/get/HTTP/1.1"2000
[1312945879]192.168.0.101:2644ipaste"GET/get/HTTP/1.1"2000
==============================================
mongrel2>stop--dbconf/config.sqlite-namemain
mongrel2>servers--dbconf/config.sqlite
SERVERS:
------
mainipaste505417b8-1de4-454f-98b6-07eb9225cca1
server2tfzhw505417b8-1de4-454f-98b6-07eb9225cca2
mongrel2>running--dbconf/config.sqlite-namemain
mongrel2atPID2854running.
mongrel2>running--dbconf/config.sqlite-namemain
mongrel2atPID3132running.
mongrel2>running--dbconf/config.sqlite-nameserver2
mongrel2atPID3191running.
mongrel2>running--dbconf/config.sqlite-namemain
[ERROR](errno:Nosuchfileordirectory)Couldn'treadthePIDfrom.//run/mongrel2.pid
mongrel2isnotrunningbecausepid_fileisn'tthere.
==============================================
mongrel2>start--dbconf/config.sqlite-namemain
[INFO](src/mime.c:49)MAXlimits.mime_ext_len=128
[INFO](src/host.c:62)MAXlimits.url_path=256,limits.host_name=256
[INFO](src/handler.c:338)MAXlimits.handler_stack=102400
[INFO](src/config/config.c:84)Loadedhandler1:tcp://127.0.0.1:9999:e884a439-31be-4f74-8050-a93565795b25:tcp://127.0.0.1:9998:
[INFO](src/config/config.c:226)Loadedroute1:/:handlerforhost1:ipaste
[INFO](src/dir.c:175)MAXlimits.dir_send_buffer=16384,limits.dir_max_path=256
[INFO](src/config/config.c:135)Loadeddirectory1:sites/ipaste/:index.html
[INFO](src/config/config.c:226)Loadedroute2:/media/:dirforhost1:ipaste
[INFO](src/config/config.c:135)Loadeddirectory1:sites/ipaste/:index.html
[INFO](src/config/config.c:226)Loadedroute3:/favicon.ico:dirforhost1:ipaste
[INFO](src/config/config.c:274)Loaded1hostsforserver1:505417b8-1de4-454f-98b6-07eb9225cca1
[INFO](src/server.c:416)LOADINGHandlertcp://127.0.0.1:9999
[INFO](src/superpoll.c:285)MAXopenfiledescriptorsis10240now.
[ERROR](src/unixy.c:99:errno:Nosuchfileordirectory)FailedtoopenPIDfile.//run/mongrel2.pidforreading.
[INFO](src/unixy.c:138)NopreviousMongrel2running,continuingon.
[INFO](src/mongrel2.c:200)Allloadedup,timetoturnintoaserver.
mongrel2>start--dbconf/config.sqlite-nameserver2
[INFO](src/mime.c:49)MAXlimits.mime_ext_len=128
[INFO](src/host.c:62)MAXlimits.url_path=256,limits.host_name=256
[INFO](src/handler.c:338)MAXlimits.handler_stack=102400
[INFO](src/config/config.c:84)Loadedhandler2:tcp://127.0.0.1:9997:e884a439-31be-4f74-8050-a93565795b24:tcp://127.0.0.1:9996:
[INFO](src/config/config.c:226)Loadedroute4:/:handlerforhost2:tfzhw
[INFO](src/dir.c:175)MAXlimits.dir_send_buffer=16384,limits.dir_max_path=256
[INFO](src/config/config.c:135)Loadeddirectory2:sites/tfzhw/:index.html
[INFO](src/config/config.c:226)Loadedroute5:/media/:dirforhost2:tfzhw
[INFO](src/config/config.c:135)Loadeddirectory2:sites/tfzhw/:index.html
[INFO](src/config/config.c:226)Loadedroute6:/favicon.ico:dirforhost2:tfzhw
[INFO](src/config/config.c:274)Loaded1hostsforserver2:505417b8-1de4-454f-98b6-07eb9225cca2
[INFO](src/server.c:416)LOADINGHandlertcp://127.0.0.1:9997
[INFO](src/superpoll.c:285)MAXopenfiledescriptorsis10240now.
[ERROR](src/unixy.c:99:errno:Nosuchfileordirectory)FailedtoopenPIDfile.//run/mongrel2_server2.pidforreading.
[INFO](src/unixy.c:138)NopreviousMongrel2running,continuingon.
[INFO](src/mongrel2.c:200)Allloadedup,timetoturnintoaserver.
==============================================
运行期控制
在m2sh提示符下，执行下面语句，会进行远程控制提示符
mongrel2>control--dbconf/config.sqlite-nameserver2
[INFO]Connectingtocontrolportipc://.//run/control
==============================================
m2[server2]>help
namehelp
stopstoptheserver(SIGINT)
reloadreloadtheserver
helpthiscommand
control_stopstopcontrolport
killkillaconnection
statusstatus,what=['net'|'tasks']
terminateterminatetheserver(SIGTERM)
timetheserver'stime
uuidtheserver'suuid
infoinformationaboutthisserver
==============================================
m2[server2]>statuswhat=net
idfdtypelast_pinglast_readlast_writebytes_readbytes_written
m2[server2]>statuswhat=tasks
idsystemnamestatestatus
1falseSERVERreadfdidle
2falseHandler_taskreadhandleridle
3falsecontrolreadhandlerrunning
4falsetickeridle
5truefdtaskyieldready
==============================================
m2[server2]>time
time:1312946823
==============================================
m2[server2]>uuid
uuid:505417b8-1de4-454f-98b6-07eb9225cca2
==============================================
m2[server2]>info
port:6768
bind_addr:0.0.0.0
uuid:505417b8-1de4-454f-98b6-07eb9225cca2
chroot:./
access_log:/logs/access_server2.log
error_log:/logs/error_server2.log
pid_file:/run/mongrel2_server2.pid
default_hostname:tfzhw
==============================================
m2[main]>statuswhat=net
idfdtypelast_pinglast_readlast_writebytes_readbytes_written
16361717171896176
937171717120525019
173916071711358117
1441171717121115019
m2[main]>killid=16
status:OK
m2[main]>killid=9
status:OK
m2[main]>killid=17
status:OK
m2[main]>killid=14
status:OK
m2[main]>statuswhat=net
idfdtypelast_pinglast_readlast_writebytes_readbytes_written
18301313104480
19311111104790
20361111106790
21371111104870
==============================================
注：使用类似m2shstart--dbconf/config.sqlite-namemain之类的命令也是可以的。