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  • 1.  Logging of DHCP requests

    Posted Sep 18, 2025 05:42 AM

    Hello,

    We have multiple campuses which are using Aruba CX 8325 or 6300 switches as DHCP servers. 

    We now have a requirement to log DHCP leases for a period of 3 months. 

    Is it possible to send the DHCP lease info to a syslog server, for example? If so, how would I do that?

    Thanks,

    Tim



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  • 2.  RE: Logging of DHCP requests

    Posted Sep 18, 2025 05:57 AM

    It's possible to configure a remote syslog server. Within the configuration you can configure a filter. Just filter on the DHCP event ID's. Please check the documentation. 

    The event information can be found in the documentation



    ------------------------------
    Willem Bargeman
    Systems Engineer Aruba
    ACEX #125
    ------------------------------

    Original Message


  • 3.  RE: Logging of DHCP requests

    Posted Sep 21, 2025 06:21 PM

    Hi Willem,

    Thanks, that looks exactly like what I am after but I seem to be missing something.

    If I run the cmd "show dhcp-server leases" I am seeing the expected leases but when I run the show events -e {event id} cmd I am not seeing any events for the leases.  

    If I disable and re-enable the DHCP server I can see those events.

     
    Thanks for your assistance.

    Tim

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    Original Message


  • 4.  RE: Logging of DHCP requests

    Posted Sep 22, 2025 03:14 AM

    Maybe another Event ID is used. Not use. Can you try find other events ID's? Request a new DHCP IP and then check the event logs using the command "show events -r | inc dhcp"



    ------------------------------
    Willem Bargeman
    Systems Engineer Aruba
    ACEX #125
    ------------------------------

    Original Message


  • 5.  RE: Logging of DHCP requests

    Posted Sep 23, 2025 03:37 PM
    Edited by Holger Hasenaug Sep 23, 2025 03:42 PM

    Hi Tim

    You need to enable DHCP-snooping like the following for every VLAN, in this case VLAN1 and disable DHCP-snooping on the uplinks pointing to your DHCP-server. 

    dhcpv4-snooping
no dhcpv4-snooping option 82
dhcpv4-snooping allow-overwrite-binding
dhcpv4-snooping event-log client
vlan 1
    dhcpv4-snooping
...
interface 1/1/12
    description uplink
    no shutdown
    vlan access 1
    dhcpv4-snooping trust

    After that you will get events like the following;

    2025-09-23T19:25:07.883487+0000 ipsavd[4407] <INFO> Event|8224|LOG_INFO|CDTR|1|Client 48:ba:4e:8b:ae:94 on vlan 1, port 1/1/1 with 16.1.1.98. Client attributes updated: Gateway 16.1.1.1, Nameserver 16.1.1.1, Lease period 864000.

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    Original Message


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