上回看了platinum的"mrtg能做些什麼"貼子，很受啟發，於是也試著做了一個。但當時對 snmpd不是很熟，所以沒有做成功，後來仔細看了一下 snmd的有關文章和RH中的/etc/snmp/snmpd.conf文件，發現用snmp+mrtg可以很好的實現對局域網內服務器狀態的監控。 現在就以用snmp+mrtg監控一台局域網內的redhat機器（IP：192.168.13.103）的網卡、內存、CPU、 DISKIO為例子，談一下如何實現。基本的法辦就是用一台redhat監控機器（IP：192.168.13.105），通過snmpwalk命令去抓目標服務器的狀態數據，然後用mrtg畫出圖來。 1、首先我們要把目標snmpd.conf文件的配好。這是用snmpwalk命令一抓取數據的關健。下面是目標機器（IP： 192.168.13.103）上的/etc/snmp/snmpd.conf文件部份內容，紅色的部份是我對snmpd.conf所做的改動。 [root@wy1 root]# cat /etc/snmp/snmpd.conf
##### First, map the community name "public" into a "security name"
# sec.name source communitycom2sec notConfigUser default public #定義community名稱為 public，映射到安全名 notConfigUser。
##### Second, map the security name into a group name:
# groupName securityModel securityNamegroup notConfigGroup v1 notConfigUser #定義安全用戶名notConfigUser映射到notConfigGroup組。group notConfigGroup v2c notConfigUser
##### Third, create a view for us to let the group have rights to: #定義一個view,來決定notConfigUser可以操作的范圍。
# Make at least snmpwalk -v 1 localhost -c public system fast again. #定義可查看的snmp的范圍。# name incl/excl suBTree mask(optional)view systemview included .1.3.6.1.2.1.1view systemview included .1.3.6.1.2.1.25.1.1[color=red:0e8fbf9ac6]view all included .1[/color:0e8fbf9ac6]##### Finally, grant the group read-only Access to the systemview view. #給notConfigGroup組所定義view名 all 以只讀權限。
# group context sec.model sec.level prefix read write notif[color=red:0e8fbf9ac6]access notConfigGroup "" any noauth exact all none none[/color:0e8fbf9ac6]#access notConfigGroup "" any noauth exact mib2 none none
# -----------------------------------------------------------------------------
# Here is a commented out example configuration that allows less# restrictive access.
# YOU SHOULD CHANGE THE "COMMUNITY" TOKEN BELOW TO A NEW KEYWord ONLY# KNOWN AT YOUR SITE. YOU *MUST* CHANGE THE NETWORK TOKEN BELOW TO# SOMETHING REFLECTING YOUR LOCAL NETWORK ADDRESS SPACE.
## sec.name source community#com2sec local localhost COMMUNITY#com2sec mynetwork NETWORK/24 COMMUNITY
## group.name sec.model sec.name#group MyRWGroup any local#group MyROGroup any mynetwork##group MyRWGroup any otherv3user#...
## incl/excl subtree mask#view all included .1 80
## -or just the mib2 tree-
#view mib2 included .iso.org.dod.internet.mgmt.mib-2 fc#view mib2 included .iso.org.dod.internet.mgmt.mib-2 fc
## context sec.model sec.level prefix read write notif#access MyROGroup "" any noauth 0 all none none#access MyRWGroup "" any noauth 0 all all all
其實配制一個snmpd.conf文件不算太難，（1）首選是定義一個共同體名(community)，這裡是public，及可以訪問這個public的用戶名（sec name），這裡是notConfigUser。Public相當於用戶notConfigUser的密碼：）# sec.name source communitycom2sec notConfigUser default public（2）定義一個組名（groupName）這裡是notConfigGroup，及組的安全級別，把notConfigGroup這個用戶加到這個組中。 groupName securityModel securityNamegroup notConfigGroup v1 notConfigUser group notConfigGroup v2c notConfigUser （3）定義一個可操作的范圍(view)名， 這裡是all，范圍是 .1 # name incl/excl subtree mask(optional) view all included .1 （4）定義notConfigUser這個組在all這個view范圍內可做的操作，這時定義了notConfigUser組的成員可對.1這個范圍做只讀操作。 # group context sec.model sec.level prefix read write notifaccess notConfigGroup "" any noauth exact all none none
ok,這樣我們的snmpd.conf文件就基本配成了，用service snmpd restart重啟snmpd服務。現在我們做一個測試，在監控機上打下面的命令： [root@wy2 root]# snmpwalk -v 1 192.168.13.103 -c public systemSNMPv2-MIB::sysDescr.0 = STRING: Linux wy1 2.4.20-8smp #1 SMP Thu Mar 13 17:45:54 EST 2003 i686SNMPv2-MIB::sysObjectID.0 = OID: NET-SNMP-MIB::netSnmpAgentOIDs.10SNMPv2-MIB::sysUpTime.0 = Timeticks: (7565377) 21:00:53.77SNMPv2-MIB::sysContact.0 = STRING: Root <[email protected]> (configure /etc/snmp/snmp.local.conf)SNMPv2-MIB::sysName.0 = STRING: wy1SNMPv2-MIB::sysLocation.0 = STRING: wy1.wuying.com (edit /etc/snmp/snmpd.conf)SNMPv2-MIB::sysORLastChange.0 = Timeticks: (10) 0:00:00.10``````````````````````“Linux wy1 2.4.20-8smp”操作系統的信息已經出來了：）現在我們在目標機上來寫一些腳本來顯標MEM、CPU、DiskIOMEM數據的抓取腳本：[root@wy1 root]# cat mfree.sh #!/bin/sh/usr/bin/free -m grep Mem awk '{print $4}'/usr/bin/free -m grep Mem awk '{print $2}'[root@wy1 root]# sh mfree.sh (上面一個數據是內存使用量，下面的是內存總量,M)442 1006CPU數據的抓取腳本[root@wy1 root]# cat cpustat.sh#!/bin/shidle=`sar -u 1 3 grep Average awk '{print $6}'`used=`echo "101 - $idle" bc -l -s`echo $usedecho $idleDiskIO數據的抓取腳本[root@wy1 root]# cat iostat.sh （顯示硬盤IO，k/s）#!/bin/shused1=`sar -d 1 3 tail -1 awk '{print $4}'`used2=`echo "$used1 / 2" bc -l`echo $used2echo $used2
好現在我們已經能得到這數據了，怎麼才能讓監控主機通過snmpd得到這些數據呢？可以在目標主機的/etc/snmp/snmpd.conf文件下面加個這些行：exec .1.3.6.1.4.1.2021.53 mfree /bin/sh /root/mfree.sh exec .1.3.6.1.4.1.2021.54 cpustat /bin/sh /root/cpustat.sh exec .1.3.6.1.4.1.2021.55 iostat /bin/sh /root/iostat.shservice snmpd restart 重啟目標主機上的snmpd服務。這樣在監控主機上運行: [root@wy2 root]# snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.53UCD-SNMP-MIB::ucdavis.53.1.1 = INTEGER: 1UCD-SNMP-MIB::ucdavis.53.2.1 = STRING: "mfree"UCD-SNMP-MIB::ucdavis.53.3.1 = STRING: "/bin/sh /root/mfree.sh"UCD-SNMP-MIB::ucdavis.53.100.1 = INTEGER: 0UCD-SNMP-MIB::ucdavis.53.101.1 = STRING: "442"UCD-SNMP-MIB::ucdavis.53.101.2 = STRING: "1006"UCD-SNMP-MIB::ucdavis.53.102.1 = INTEGER: 0其中UCD-SNMP-MIB::ucdavis.53.101.1 = STRING: "442" 中的442就是mfree.sh輸出的第一個數據，1006是mfree.sh輸出的第二個數據。OK，再做一下加工：[root@wy2 root]# snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.53 grep 53.101 awk -F\" '{print $2}'4431006好，我們已經通過snmpd從監控主機上得到了目標主機上內存使用的這兩個數據了：）,其它的兩個腳本也一樣： CPU使用、空閒。[root@wy2 root]# snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.54 grep 54.101 awk -F\" '{print $2}'1.1799.83 DISK IO 狀態：[root@wy2 root]# snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.55 grep 55.101 awk -F\" '{print $2}'43.0000000000000000000043.00000000000000000000
最後是編輯監控主機上的mrtg.cfg文件，在Target[xxxx]中加入上面的命令，下面是我的mrtg.cfg文件，前面的兩個 Target是我用/usr/bin/cfgmaker --global 'WorkDir: /home/httpd/mrtg/net' -- global 'Options[_]:growright,bits' --ifref=ip [email protected] 命令生成的，後面的是我跟據platinum 的"mrtg能做些什麼"的貼子內的mrtg.cfg文件改的。（在精華裡，大家可以看一下）。[root@wy1 root]# cat /home/httpd/mrtg/103/mrtg.cfg # Created by # /usr/bin/cfgmaker --global 'WorkDir: /home/httpd/mrtg/net' --global 'Options[_]:growright,bits' --ifref=ip [email protected]
### Global Config Options
# for UNIX# WorkDir: /home/http/mrtg
# or for NT# WorkDir: c:\mrtgdata
### Global Defaults
# to get bits instead of bytes and graphs growing to the right# Options[_]: growright, bits
WorkDir: /home/httpd/mrtg/103Options[_]:growright,bitsLanguage: chinese####################################################################### System: wy1# Description: Linux wy1 2.4.20-8smp #1 SMP Thu Mar 13 17:45:54 EST 2003 i686# Contact: Root <[email protected]> (configure /etc/snmp/snmp.local.conf)# Location: wy1.wuying.com (edit /etc/snmp/snmpd.conf)######################################################################
### Interface 2 >> Descr: 'eth0' Name: '' Ip: '192.168.13.103' Eth: '00-06-5b-19-9d-ea' ###
Target[192.168.13.103_192.168.13.103]: /192.168.13.103:[email protected]:SetEnv[192.168.13.103_192.168.13.103]: MRTG_INT_IP="192.168.13.103" MRTG_INT_DESCR="eth0"MaxBytes[192.168.13.103_192.168.13.103]: 1250000Xsize[192.168.13.103_192.168.13.103]: 300Ysize[192.168.13.103_192.168.13.103]: 100#kmg[192.168.13.103_192.168.13.103]: K/s,M/s#kilo[192.168.13.103_192.168.13.103]: 1024Title[192.168.13.103_192.168.13.103]: Traffic for eth0 192.168.13.103 -- wy1PageTop[192.168.13.103_192.168.13.103]: <H1>Traffic for eth0 192.168.13.103 -- wy1</H1>#Options[192.168.13.103_192.168.13.103]: growright,gauge,nopercent
### Interface 3 >> Descr: 'eth1' Name: '' Ip: '172.16.0.188' Eth: '00-06-5b-19-9d-e9' ###
Target[192.168.13.103_172.16.0.188]: /172.16.0.188:[email protected]:SetEnv[192.168.13.103_172.16.0.188]: MRTG_INT_IP="172.16.0.188" MRTG_INT_DESCR="eth1"Xsize[192.168.13.103_172.16.0.188]: 300Ysize[192.168.13.103_172.16.0.188]: 100MaxBytes[192.168.13.103_172.16.0.188]: 1250000#ShortLegend[192.168.13.103_172.16.0.188]: #kmg[192.168.13.103_172.16.0.188]: b/s,Kb/s#kilo[192.168.13.103_172.16.0.188]: 1024Title[192.168.13.103_172.16.0.188]: Traffic for eth1 172.16.0.188 -- wy1PageTop[192.168.13.103_172.16.0.188]: <H1>Traffic for eth1 172.16.0.188 -- wy1</H1>#Options[192.168.13.103_172.16.0.188]: growright,gauge,nopercent
###MEM status
Target[wy1_mem]:`snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.53 grep 53.101 awk -F\" '{print $2}'`#Targey[wy1_mem]: memTotalReal.0&memAvailReal.0:[email protected][wy1_mem]: 300Ysize[wy1_mem]: 100Ytics[wy1_mem]: 7MaxBytes[wy1_mem]: 1006Title[wy1_mem]:Memory State of WY1 IP 192.168.13.103 ServerPageTop[wy1_mem]:<H1>Memory State of WY1 IP 192.168.13.103 Server</H1>ShortLegend[wy1_mem]: MBkmg[wy1_mem]: MBkilo[wy1_mem]:1024YLegend[wy1_mem]: Memory UsageLegend1[wy1_mem]: 可用內存Legend2[wy1_mem]: 總內存量Legend3[wy1_mem]: 可用內存Legend4[wy1_mem]: 總內存量LegendI[wy1_mem]: 可用內存LegendO[wy1_mem]: 總內存量Options[wy1_mem]: growright,gauge,nopercent
###cpu statusTarget[wy1_CPU]:`snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.54 grep 54.101 awk -F\" '{print $2}'`#Targey[wy1_CPU]: memTotalReal.0&memAvailReal.0:[email protected][wy1_CPU]: 300Ysize[wy1_CPU]: 100Ytics[wy1_CPU]: 7MaxBytes[wy1_CPU]: 100Title[wy1_CPU]:CPU State of WY1 IP 192.168.13.103 ServerPageTop[wy1_CPU]:<H1>CPU State of WY1 IP 192.168.13.103 Server</H1>ShortLegend[wy1_CPU]: kmg[wy1_CPU]: %#kilo[wy1_CPU]:1024YLegend[wy1_CPU]: CPU Usage Legend1[wy1_CPU]: 已用CPU: Legend2[wy1_CPU]: 可用CPU: LegendI[wy1_CPU]: 已用CPU: LegendO[wy1_CPU]: 可用CPU: Options[wy1_CPU]: growright,gauge,nopercent
###iostat###cpu statusTarget[wy1_IO]:`snmpwalk -v 1 192.168.13.103 -c public .1.3.6.1.4.1.2021.55 grep 55.101 awk -F\" '{print $2}'`#Targey[wy1_IO]: memTotalReal.0&memAvailReal.0:[email protected][wy1_IO]: 300Ysize[wy1_IO]: 100Ytics[wy1_IO]: 7MaxBytes[wy1_IO]: 10000Title[wy1_IO]: DISK IO State of WY1 IP 192.168.13.103 ServerPageTop[wy1_IO]:<H1>DISK IO State of WY1 IP 192.168.13.103 Server</H1>ShortLegend[wy1_IO]: kmg[wy1_IO]: K/s,M/skilo[wy1_IO]:1024YLegend[wy1_IO]: DISK IO SPEEDLegend1[wy1_IO]: IO速度:Legend2[wy1_IO]: IO速度:LegendI[wy1_IO]: IO速度:LegendO[wy1_IO]: IO速度:Options[wy1_IO]: growright,gauge,nopercent
用indexmaker -o /home/httpd/mrtg/103/index.Html /home/httpd/mrtg/103/mrtg.cfg 生成網頁，在crontab 中加入*/5 * * * * mrtg /home/httpd/mrtg/103/mrtg.cfg OK，這樣我們就能通過mrtg生成的圖來監控我們linux的機器的狀態了。在IE中打入http: //192.168.13.105/mrtg/103,mrtg的監控網頁就出來啦（/home/httpd/是我appache的主目錄）。當然我們也能用snmpwalk命令來得到安裝有snmp服務的win2000機器的狀態的數據：如：
[root@wy1 103]# snmpwalk -v 1 192.168.1.5 -c public HOST-RESOURCES-MIB::hrStorage HOST-RESOURCES-MIB::hrMemorySize.0 = INTEGER: 3800424 KBytesHOST-RESOURCES-MIB::hrStorageIndex.1 = INTEGER: 1HOST-RESOURCES-MIB::hrStorageIndex.2 = INTEGER: 2HOST-RESOURCES-MIB::hrStorageIndex.3 = INTEGER: 3HOST-RESOURCES-MIB::hrStorageIndex.4 = INTEGER: 4HOST-RESOURCES-MIB::hrStorageIndex.5 = INTEGER: 5HOST-RESOURCES-MIB::hrStorageIndex.6 = INTEGER: 6HOST-RESOURCES-MIB::hrStorageType.1 = OID: HOST-RESOURCES-TYPES::hrStorageRemovableDiskHOST-RESOURCES-MIB::hrStorageType.2 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDiskHOST-RESOURCES-MIB::hrStorageType.3 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDiskHOST-RESOURCES-MIB::hrStorageType.4 = OID: HOST-RESOURCES-TYPES::hrStorageFixedDiskHOST-RESOURCES-MIB::hrStorageType.5 = OID: HOST-RESOURCES-TYPES::hrStorageCompactDiscHOST-RESOURCES-MIB::hrStorageType.6 = OID: HOST-RESOURCES-TYPES::hrStorageVirtualMemoryHOST-RESOURCES-MIB::hrStorageDescr.1 = STRING: A:\HOST-RESOURCES-MIB::hrStorageDescr.2 = STRING: C:\ Label: Serial Number 581e89feHOST-RESOURCES-MIB::hrStorageDescr.3 = STRING: D:\ Label:New Volume Serial Number 1cde6e55HOST-RESOURCES-MIB::hrStorageDescr.4 = STRING: E:\ Label:DATA_BAK Serial Number 30d29147HOST-RESOURCES-MIB::hrStorageDescr.5 = STRING: F:\HOST-RESOURCES-MIB::hrStorageDescr.6 = STRING: Virtual MemoryHOST-RESOURCES-MIB::hrStorageAllocationUnits.1 = INTEGER: 0 BytesHOST-RESOURCES-MIB::hrStorageAllocationUnits.2 = INTEGER: 4096 BytesHOST-RESOURCES-MIB::hrStorageAllocationUnits.3 = INTEGER: 4096 BytesHOST-RESOURCES-MIB::hrStorageAllocationUnits.4 = INTEGER: 4096 BytesHOST-RESOURCES-MIB::hrStorageAllocationUnits.5 = INTEGER: 0 BytesHOST-RESOURCES-MIB::hrStorageAllocationUnits.6 = INTEGER: 65536 BytesHOST-RESOURCES-MIB::hrStorageSize.1 = INTEGER: 0HOST-RESOURCES-MIB::hrStorageSize.2 = INTEGER: 2050287HOST-RESOURCES-MIB::hrStorageSize.3 = INTEGER: 15703529HOST-RESOURCES-MIB::hrStorageSize.4 = INTEGER: 53263499HOST-RESOURCES-MIB::hrStorageSize.5 = INTEGER: 0HOST-RESOURCES-MIB::hrStorageSize.6 = INTEGER: 89444HOST-RESOURCES-MIB::hrStorageUsed.1 = INTEGER: 0HOST-RESOURCES-MIB::hrStorageUsed.2 = INTEGER: 1233681HOST-RESOURCES-MIB::hrStorageUsed.3 = INTEGER: 591593HOST-RESOURCES-MIB::hrStorageUsed.4 = INTEGER: 23583930HOST-RESOURCES-MIB::hrStorageUsed.5 = INTEGER: 0HOST-RESOURCES-MIB::hrStorageUsed.6 = INTEGER: 50611HOST-RESOURCES-MIB::hrStorageAllocationFailures.1 = Counter32: 0HOST-RESOURCES-MIB::hrStorageAllocationFailures.2 = Counter32: 0HOST-RESOURCES-MIB::hrStorageAllocationFailures.3 = Counter32: 0HOST-RESOURCES-MIB::hrStorageAllocationFailures.4 = Counter32: 0HOST-RESOURCES-MIB::hrStorageAllocationFailures.5 = Counter32: 0HOST-RESOURCES-MIB::hrStorageAllocationFailures.6 = Counter32: 0上面顯示的是192.168.1.5這台win2000SERVER的磁盤信息，可以看到盤符、每個分區的空間總量、使用量等。其它的相應建值還有：Diskused: HOST-RESOURCES-MIB::hrStorageUsedCPU: HOST-RESOURCES-MIB::hrProcessorLoadRUN Proc: HOST-RESOURCES-MIB::hrSWRunNameSYS Uptime: HOST-RESOURCES-MIB::hrSystemUptime SNMPv2-MIB::sysUpTimeSYS Date: HOST-RESOURCES-MIB::hrSystemDateSYS Device: HOST-RESOURCES-MIB::hrDeviceDescrSYS Descr: SNMPv2-MIB::sysDescrSYS Name: SNMPv2-MIB::sysNamenetcard speed: IF-MIB::ifSpeednetcard physcal address: IF-MIB::ifPhysAddress這樣我們就可以用一台linux主機通過snmp+mrtg來監控多台局域網內的linux/win2000SERVER了：）。現在我最關心的是如何讓snmp包穿過防火牆，（我用snmpwalk試了一下，抓不到公司在IDC防火牆後的SERVER的snmp數據）。不然，我就可以用snmp去監控公司在IDC防火牆後的SERVER的狀態了。聽說perl能實現，但不知用什麼樣的方法來實現？
作者：eagerlinuxer