Solved: Can't in/decrease DHCP range; "IP address is in th... - Check Point CheckMates

Can't in/decrease DHCP range; "IP address is in the range of an existing network"

Hello folks,

I can't change the dhcp range on a CP 1450 appliance; "IP address is in the range of an existing network". I don't see that anything overlaps with the range.

Deactivating/ reactivating DHCP and rebooting was of no help. The firmware is up to date.

Please see attached screenshots; no matter if I try to increase or decrease the DHCP-scope, error stays the same.

Am I doing something wrong here or is this a bug?

Thanks in advance!

Appliance:Check Point 1450 Appliance (rmg-oregon-fw01)

Security Management:Locally managed

Version (Firmware):R77.20.70 (990171948)

lan.PNG

Preview file

35 KB

dhcp-err.PNG

Preview file

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1 Solution

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G_W_Albrecht

MVP Silver

‎2018-02-0803:35 AM

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This error is the "IP address is in the subnet of an existing network" error (not range), and according to the available documentation, this could be the bug from sk111840 VTI creation on SMB Appliance fails with "IP address is in the subnet of an existing network" error, but as you use R77.20.70 and it was already resolved in R77.20.40 firmware, it looks to me as Dameon wrote - either a configuration error or a new bug .

CCSP - CCSE / CCTE / CTPS / CCME / CCSM Elite / SMB Specialist

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3 Replies

PhoneBoy

Admin

‎2018-01-1902:56 PM

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When I've seen this error, it's because the subnet may be in use by some other interface.

Worst case, I recommend engaging with the TAC: Contact Support | Check Point Software

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G_W_Albrecht

MVP Silver

‎2018-02-0803:35 AM

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CCSP - CCSE / CCTE / CTPS / CCME / CCSM Elite / SMB Specialist

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Julius_Kaiser

Participant

‎2018-04-1702:47 AM

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Thank you guys! CP ruled out configuration errors here and approved an RMA.

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