Problems to receive DHCP address

Frequently Asked Questions
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jono
Posts: 85
Joined: 18 Apr 2008, 10:46
Location: Clavister HQ - Örnsköldsvik

Problems to receive DHCP address

Post by jono » 21 Apr 2008, 12:57

This FAQ applies to:
  • Clavister Security Gateway 8.x and up
Symptom:
The Security Gateway fails to receive an IP address from DHCP.

Solution:
The Security Gateway has some settings that could be altered in order to get the DHCP client to work.

The default settings in advanced settings->DHCP client is following:

Note: Path is Network->Interfaces and VPN->Ethernet->Advanced Settings in version 10.x and up.
  • DHCP_MinimumLeaseTime 60
    DHCP_ValidateBcast YES
    DHCP_AllowGlobalBcast NO
    DHCP_UseLinkLocalIP NO
    DHCP_DisableArpOnOffer NO
However. To have the Security Gateway accept uncommon IP offers you might have to make adjustments on the settings.
  • DHCP_MinimumLeaseTime 60
    DHCP_ValidateBcast NO
    DHCP_AllowGlobalBcast YES
    DHCP_UseLinkLocalIP NO
    DHCP_DisableArpOnOffer YES
Note: The swedish ISP Telia has some servers that causes problems with the default settings. Changing the settings to the following is known to work in those cases:
  • DHCP_MinimumLeaseTime 60
    DHCP_ValidateBcast NO
    DHCP_AllowGlobalBcast YES
    DHCP_UseLinkLocalIP NO
    DHCP_DisableArpOnOffer NO
In older Clavister Security Gateways there was an option to not set the default gateway before lease. This should be set to yes in the Telia case.

Note2: The swedish ISP COMHem has in some cities changed the minimum lease time to 30. Changing the settings to the following is known to work in those cases:
  • DHCP_MinimumLeaseTime 30
    DHCP_ValidateBcast NO
    DHCP_AllowGlobalBcast YES
    DHCP_UseLinkLocalIP NO
    DHCP_DisableArpOnOffer NO

mape
Posts: 41
Joined: 24 Oct 2016, 08:23

Re: Problems to receive DHCP address

Post by mape » 30 Nov 2016, 11:12

Note3: If having problems retrieving DHCP lease from the German provider Vodafone/Kabel Deutschland, a possible workaround would be to change the MAC Address of the connected interface. An example would be to use a MAC address in any of the following ranges:

x2:xx:xx:xx:xx:xx
x6:xx:xx:xx:xx:xx
xA:xx:xx:xx:xx:xx
xE:xx:xx:xx:xx:xx

or

52:54:00:xx:xx:xx

1. Create a new object: Go to Objects -> Address Book -> Add new Ethernet Address -> Set name and your new MAC Address.

2. Apply the earlier created MAC Address by going to: Network -> Interfaces and VPN -> Link Layer -> Ethernet -> <Interface> -> Hardware settings -> Manual MAC Address and select your new object.

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