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AhmedWas
Asked: 2023-07-07 17:38:30 +0800 CST

DHCP renewal can't go through because DHCP server is down

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To my experience, if a DHCP client tries to renew its lease, but the DHCP server is down, and after the lease time is over, there are two possible scenarios:

  1. The client keeps the IP
  2. The client goes back to INIT state

I've seen the two scenarios before with different vendors.

I can't find exactly which one is according to the standard. Can someone help? Thanks!

dhcp

1 Answers

  1. Best Answer

    Renewal usually happens before expiration - most often starting at 50% lease time.

    If the lease eventually expires before a renewal can be DHCPACKed, the client must not continue to use the leased address. It must re-enter the INIT phase from before the lease.

    See RFC 2131 section 4.4.5 for details.

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