Configuring NTP Server on a Cisco WLC via CLI

You'll need to configure a Cisco WLC using the CLI in case the routing to the network where you HTTPS or access the GUI is unreachable. In my case only the management server is able to SSH remotely to the WLC.

You can verify if the AP has successfully joined the WLC using the show ap join stats summary all command.

(Cisco Controller) >show ap join stats summary all

Number of APs.............................................. 5

Base Mac             AP EthernetMac       AP Name                 IP Address         Status
c4:b9:cd:1f:02:ab    N A                  AP2c5a.0f5a.fabc        10.16.25.24      Not Joined
c4:b9:cd:1f:08:cd   N A                  AP2c5a.0f5a.fdef         10.16.25.30      Not Joined
c4:b9:cd:1f:17:ef    N A                  AP2c5a.0f5a.f123       10.16.25.26      Not Joined
c4:b9:cd:1f:1c:12    N A                  AP2c5a.0f5a.f456       10.16.25.27      Not Joined
c4:b9:cd:1f:22:34    N A                  AP2c5a.0f5a.f789        10.16.25.25      Not Joined


Use the show time command to verify if an NTP server is configured and synchronized time on the WLC.

(Cisco Controller) >show time

Time............................................. Sat Jan  1 11:54:25 2000     // DATE AND YEAR NOT SYNC'D
Timezone delta................................... 0:0
Timezone location................................ (GMT +8:00) HongKong, Bejing, Chongquing

NTP Servers
    NTP Polling Interval.........................     3600

     Index     NTP Key Index                  NTP Server                  NTP Msg Auth Status
    -------  ----------------------------------------------------------------------------------
       1              0                                63.12.7.2                           AUTH DISABLED


I tried to ping the configured NTP server and Google's public NTP server but it's not reachable.

(Cisco Controller) >ping 63.12.7.2    

Send count=3, Receive count=0 from 63.12.7.2

(Cisco Controller) >ping 216.239.35.4      // GOOGLE NTP

Send count=3, Receive count=0 from 216.239.35.4


I've configured another internal NTP server that is reachable from the site using the config time ntp server command.

(Cisco Controller) >ping 10.12.3.4

Send count=3, Receive count=3 from 10.12.3.4

(Cisco Controller) >config time ?
              
manual         Configures the system time.
ntp            Configures the Network Time Protocol.
timezone       Configures the system's timezone.
              
(Cisco Controller) >config time ntp ?
              
auth           Configures the NTP authentication
interval       Configures the Network Time Protocol Polling Interval.
key-auth       Configures the NTP authentication key.
server         Configures the Network Time Protocol Servers.
              
(Cisco Controller) >config time ntp server ?
              
<index>        Enter NTP server index.
              
(Cisco Controller) >config time ntp server 1 ?
              
<IP Address>   Enter NTP server's IP address. Use 0.0.0.0 to delete entry
              
(Cisco Controller) >config time ntp server 1 10.12.3.4


The DTLS tunnel on the AP were established and it was able to join the WLC.

(Cisco Controller) >show ap join stats summary all

Number of APs.............................................. 5

Base Mac             AP EthernetMac       AP Name                 IP Address         Status
c4:b9:cd:1f:02:ab    N A                  AP2c5a.0f5a.fabc        10.16.25.24         Joined
c4:b9:cd:1f:08:cd   N A                  AP2c5a.0f5a.fdef         10.16.25.30         Joined
c4:b9:cd:1f:17:ef    N A                  AP2c5a.0f5a.f123       10.16.25.26          Joined
c4:b9:cd:1f:1c:12    N A                  AP2c5a.0f5a.f456       10.16.25.27         Joined
c4:b9:cd:1f:22:34    N A                  AP2c5a.0f5a.f789        10.16.25.25        Joined


(Cisco Controller) >save config       // SAVE THE CONFIG IN NVRAM

Are you sure you want to save? (y/n) y

Configuration Saved!