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  • 1.  EX switch sending chassis serial number to DHCP server instead of hostname

    Posted 10-07-2021 13:23
    Hey there,

    I have a few new EX devices(EX4300/EX3200) that I'm throwing on a management network using their me0 physical management interfaces. Management network has a DHCP server that puts the switch hostnames in DNS. The issue is each device sends its chassis serial number to the DHCP server instead of the device hostname(I need the switch hostname in DNS, not the S/n). I have observed the same behavior on JUNOS 18.2R3 and 20.4R1. Any ideas?

    me0.0 config (device hostname visible):

    DHCPREQUEST packet from EX device to DHCP server showing serial number as device hostname:

    Chassis S/N:




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  • 2.  RE: EX switch sending chassis serial number to DHCP server instead of hostname

    Posted 10-08-2021 05:07

    Each me0 has a unique MAC. Reserve the MAC in DHCP to get the IP address you want for that device.

    You can also just statically assign the IP and forget about DHCP no?

    Having  DHCP assign different addresses is only useful if you remove the switch from, say Datacenter A to B. That second DHCP scope in DC 2 would give a new IP for that scope and a DNS name is associated with that new IP.

    Maybe it would be useful if you have a datacenter redesign, but that doesn't happen all the time!

    But static is fine if the switch will never move.

    -Ambi




  • 3.  RE: EX switch sending chassis serial number to DHCP server instead of hostname

    Posted 10-11-2023 22:45

    I have the same issue with QFX switches, did you ever find a way to properly report hostname to the DHCP server?



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