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八克里: 在 CentOS 7 安裝 snmpd 服務(CentOS 7 SNMP install)
How To Install and Configure SNMP on RHEL 7 or CentOS 7
為了使用 cacti 和 nagios 來監測系統主機，隨時掌握主機及服務的存活狀態，所以加裝 snmpd 服務。
1. 安裝 snmpd 所需套件
# yum install net-snmp net-snmp-utils
2. 備份原設定檔 /etc/snmp/snmpd.conf
# cp /etc/snmp/snmpd.conf /etc/snmp/snmpd.conf.$(date +%F)[@more@]
3. 修改 /etc/snmp/snmpd.conf 設定檔
# grep -v “^$” /etc/snmp/snmpd.conf | grep -v ‘^ *#’
com2sec notConfigUser default public
group notConfigGroup v1 notConfigUser
group notConfigGroup v2c notConfigUser
view systemview included .1.3.6.1.2.1.1
view systemview included .1.3.6.1.2.1.25.1.1
access notConfigGroup “” any noauth exact systemview none none
syslocation Unknown (edit /etc/snmp/snmpd.conf)
syscontact Root <root@localhost> (configure /etc/snmp/snmp.local.conf)
dontLogTCPWrappersConnects yes
或
將 41/47/48/55/56/62 行註解
# sed -i ’41s/^/#/’ /etc/snmp/snmpd.conf
# sed -i ’47s/^/#/’ /etc/snmp/snmpd.conf
# sed -i ’48s/^/#/’ /etc/snmp/snmpd.conf
# sed -i ’55s/^/#/’ /etc/snmp/snmpd.conf
# sed -i ’56s/^/#/’ /etc/snmp/snmpd.conf
# sed -i ’62s/^/#/’ /etc/snmp/snmpd.conf
取消 112,116~117,122~126,129~130,141~145,147 前面的註解
# sed -i ‘112s/^#//’ /etc/snmp/snmpd.conf
# sed -i ‘116,117s/^#//’ /etc/snmp/snmpd.conf
# sed -i ‘122,126s/^#//’ /etc/snmp/snmpd.conf
# sed -i ‘129,130s/^#//’ /etc/snmp/snmpd.conf
# sed -i ‘141,145s/^#//’ /etc/snmp/snmpd.conf
# sed -i ‘147s/^#//’ /etc/snmp/snmpd.conf
取消 151 行前面註解，並將rwview 改成 none
# sed -i -e ‘151s/^#//’ -e ‘s/rwview/none/’ /etc/snmp/snmpd.conf
4. 啟動 snmpd 服務及設定開機時啟動
# systemctl start snmpd.service
# systemctl enable snmpd.service
Created symlink from /etc/systemd/system/multi-user.target.wants/snmpd.service to /usr/lib/systemd/system/snmpd.service.
5. 檢查 snmpd 是否有正常啟動
# netstat -auntp | grep snmp
tcp 0 0 127.0.0.1:199 0.0.0.0:* LISTEN 1822/snmpd
udp 0 0 0.0.0.0:161 0.0.0.0:* 1822/snmpd
6. 防火牆上的設定，最好要設定可以連線的範圍
# firewall-cmd –permanent –add-port=161/udp
success
# firewall-cmd –reload
success
# firewall-cmd –list-all
public (default, active)
interfaces: eno16777736
sources:
services: dhcpv6-client ftp samba ssh
ports: 21/tcp 161/udp
masquerade: no
forward-ports:
icmp-blocks:
rich rules:
7. 進行本機上的測試
# snmpwalk -v 1 -c public -O e 127.0.0.1
# snmpwalk -c public -v 2c 127.0.0.1