Re: [PATCH 4.4 0/5] DHCP client support when receiving "delayed" replies
Patryk Mungai Ndungu <patryk.mungai-ndungu.kx@...>
Hello Pavel,toggle quoted messageShow quoted text
-----Original Message-----It varies: the fastest reply I've seen is 0.12931s, the slowest is in the region is just over 1.007s.
In the tests I've run, I measured the time between the kernel sending out the DHCP request and receiving a DHCP offer from the server. After running 50 tests, in around half of them, it takes just over 1s for the DHCP offer to arrive. But this is rarely over 1s +1 jiffie, hence why I think the code is able to cope with it most of the time.
However, the DHCP servers network is not at all loaded (at most only has 4 devices trying to connect to it at once), and yet I've seen this failure multiple times, so I'm not sure what would happen in a loaded network.
I think at least for CIP we need a kernel that is able to cope with however long the server takes to reply.
Can you solve the problemI've tried increasing CONF_INTER_TIMEOUT to 2Hz and I haven't seen it fail in 50 boots. Though this is an simple workaround, it can prolong boot up time and the DHCP client is still time dependent with regards to listening for a reply on a network device.