Problem Description
Our users are facing disconnections to the applications connected whenNAC is applied and also observed gateway is also not reachable during theissue.
Problem Analysis
As today remotesession, we can see all the terminals offline reason is “ARP detect fail” asfollow
<CTS_CHN_T-NAGAR_SW2_4TH_F>display offline-record all
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Username :141877b3cae7
Domainname : default
UserMAC : 1418-77b3-cae7
User accesstype : MAC
User accessinterface : GigabitEthernet0/0/20
Qinqvlan/User vlan : 0/10
User IPaddress : 192.168.228.48
User IPV6address : FE80::137:70C4:B95B:906C
UserID : 550
User logintime : 2018/09/28 13:56:41
Useroffline time : 2018/09/28 14:43:53
User offline reason : ARP detect fail
According to thereason, so we configure the below command
access-userarp-detect vlan 10 ip-address 192.168.228.6 mac-address 0000-0c07-ac0a
Thenthe terminal disconnect(plug-out cable) and connect again, we observe more than10 minutes, didn’t disconnect again, seems fine.
Pleasekeep observing, once any news, please update us.
Another thing, please note: once any fault terminal,please disconnect(plug-out cable) and connect again, then that command can beeffective and issue can be solved.
Root Cause
Once the ip-phonedon’t use for a period of time, the gateway will detect the terminal failed,then make terminal offline, so we can see the offline reason is “ARP detectfail”
Solution Description
Once the ip-phonedon’t use for a period of time, the gateway will detect the terminal failed,then make terminal offline. After the period of time, customer want to use theip-phone again, then it will re-authenticateagain. So occurred previous issue.
So we need configurethe below command to detect the terminal all the time, then it will not beoffline.
access-userarp-detect vlan 10 ip-address 192.168.228.6 mac-address 0000-0c07-ac0a
