IOS
Cisco IOS Software, C3750E Software (C3750E-UNIVERSALK9-M), Version 12.2(55)SE5, RELEASE SOFTWARE (fc1)
故障现象：
故障接口插不插网线指示灯都为 桔红色，查看接口状态为
#sh interfaces status Port Name Status Vlan Duplex Speed Type Gi1/0/48 err-disabled 1 auto auto 10/100/1000BaseTX
原因查找：
查看err-disable原因 #show interface status err-disable Port Name Status Reason Err-disabled Vlans Gi1/0/48 err-disabled loopback loopback，看来是环路了 #看看具体配置 #查看针对哪些功能开启了err检测 #sh errdisable detect ErrDisable Reason Detection Mode ----------------- --------- ---- arp-inspection Enabled port bpduguard Enabled port channel-misconfig (STP) Enabled port community-limit Enabled port dhcp-rate-limit Enabled port dtp-flap Enabled port gbic-invalid Enabled port inline-power Enabled port invalid-policy Enabled port l2ptguard Enabled port link-flap Enabled port loopback Enabled port lsgroup Enabled port mac-limit Enabled port pagp-flap Enabled port port-mode-failure Enabled port pppoe-ia-rate-limit Enabled port psecure-violation Enabled port/vlan security-violation Enabled port sfp-config-mismatch Enabled port small-frame Enabled port storm-control Enabled port udld Enabled port vmps Enabled port #检测到err后是否重启接口，重启接口的间隔时间是多少 #sh errdisable recovery ErrDisable Reason Timer Status ----------------- -------------- arp-inspection Disabled bpduguard Disabled channel-misconfig (STP) Disabled dhcp-rate-limit Disabled dtp-flap Disabled gbic-invalid Disabled inline-power Disabled l2ptguard Disabled link-flap Disabled mac-limit Disabled loopback Disabled pagp-flap Disabled port-mode-failure Disabled pppoe-ia-rate-limit Disabled psecure-violation Disabled security-violation Disabled sfp-config-mismatch Disabled small-frame Disabled storm-control Disabled udld Disabled vmps Disabled Timer interval: 300 seconds Interfaces that will be enabled at the next timeout:
恢复接口：
#关闭再打开接口就行了 #interface Gi1/0/48 #shutdown #no shutdown