Losing DHCP Gateway

Question

This problem started with 17.5.0 GA. The firewall is handling DHCP for my lan. Users have started to lose the default gateway(the Firewall) randomly throughout the day. I have to either reset the switch or the desktop network adapter in order to regain internet connectivity. This does NOT happen to all users at the same time. 
 I updated to XG 115 SFOS 17.5.5 MR5 but the problem still exists. This actually introduced another problem of not being able to access the gui from Sophos Central, but that's not as pressing. Any thoughts on this would be appreciated. 
 Thanks 
 Larnel

deeptibhavsar · Accepted Answer

Hi, 
 Thank you for the feedback. 
 Request to run below command from CLI, in case of facing issue & give us feedback. 
 console> system dhcp conf-generation-method old 
 
 It seems, the reported issue NC-46351, which will be fixed with next MR release. 
 
 Regards, 
 Deepti

Big_Buck · Answer

I run MR8 on new DHCP method since MR8 was released. 
 Runs smoot up to now. 
 Paul Jr

deeptibhavsar · Answer

Hi All, 
 Thank you for your regress feedback & support 
 With MR6, we have been closed with JIRA ID NC-46351, which was earlier reported. 
 We are working on the JIRA ID NC-48031, till now please use the CLI to switch the DHCP old config generate method. 
 
 Regards, 
 Deepti

LuCar Toni · Answer

This issue has now been resolved in SFOS v17.5.8: 
 https://community.sophos.com/products/xg-firewall/b/blog/posts/sfos-17-5-mr8-released 
 
 NC-48031 [Interface Management] Wifi client did not get gateway and other config after reboot until enable and re-enable the wifi on client

BLS · Answer

Re-running the command above resolved the problem again, so I can confirm it hasn't been fixed in the MR6 release.

Big_Buck · Answer

Hello 
 The command is "system dhcp ... " and not "dhcp system ...". 
 
 Paul Jr

Tibor Soós · Answer

Actually i rebuilded the XG Firewall on Intel hardware (and finished with the Hyper-V one) with the latest firmware and its working without any issue.

JacobRodriguez · Answer

Changing the dhcp to the old method using the command line console is still working for me a month later. I can see how increase the lease team would work also.

Command: 
 console> system dhcp conf-generation-method old