Re: DHCP Automatic Configure at Driver Connect

["Wu, Jiaxin" <jiaxin.wu@intel.com>]

Eugene,

The default policy is static,  DHCPSB will not be installed automatically. Currently, there are only two cases that DHCP process will be triggered. One is Ip4Config2 policy change to DHCP, and another one is any IP4 configure instance set UseDefaultAddress to TRUE, detailed see Ip4StartAutoConfig().  So, I don't quite understand your question about the differs behavior compared to before. I think the current behavior of Ip4Config2 DHCP also need the third specifically configuration.

Thanks,
Jiaxin

> -----Original Message-----
> From: Cohen, Eugene [mailto:eugene@hp.com]
> Sent: Thursday, August 11, 2016 2:17 AM
> To: edk2-devel@lists.01.org; Wu, Jiaxin <jiaxin.wu@intel.com>
> Subject: DHCP Automatic Configure at Driver Connect
> 
> With this commit:
> 
> Revision: 1f6729ffe98095107ce82e67a4a0209674601a90
> Author: jiaxinwu <jiaxin.wu@intel.com>
> Date: 7/7/2015 2:19:55 AM
> Message:
> MdeModulePkg: Update Ip4Dxe driver to support Ip4Config2 protocol,
> 
> a new behavior seemed to come in to the network stack that was not
> present before: It appears now that as soon as the DHCP Service Binding
> protocol is installed the DHCP process will be initiated (see
> Ip4Config2OnDhcp4SbInstalled).  This differs from past behavior where DHCP
> would only occur if a driver or application specifically did Configure() on the
> network interface.
> 
> For some systems this is problematic because they need to defer DHCP until
> it is certain that the network interface will be used for something.
> 
> Can you provide the reason for this change?  Can we have a policy (PCD) to
> disable this mode of operation?
> 
> Thanks,
> 
> Eugene
>