[lwip-devel] [patch #9858] dhcp/dhcp6: Ensure that DHCP/DHCPv6 DNS server updates don't overlap

[David J. Fiddes]

URL:
  <https://savannah.nongnu.org/patch/?9858>

                 Summary: dhcp/dhcp6:  Ensure that DHCP/DHCPv6 DNS server
updates don't  overlap
                 Project: lwIP - A Lightweight TCP/IP stack
            Submitted by: davefiddes
            Submitted on: Thu 03 Oct 2019 12:05:06 PM UTC
                Category: None
                Priority: 5 - Normal
                  Status: None
                 Privacy: Public
             Assigned to: None
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
         Planned Release: None

    _______________________________________________________

Details:

This change changes the DHCP and DHCPv6 DNS server option update
processing so that both IPv4 and IPv6 servers can be held in the
list of active DNS servers. Previously when a DHCP offer is processed
the list of active DNS servers is replaced. This can lead to failed
DNS resolution when there is a connectivity over one IP protocol
but not over the other. This change improves the possibility of
DNS resolution falling back to a working DNS server.

Tests:
 - On LWIP configured to use 2 DNS server entries. Configure DHCP and
   DHCPv6 to have 0,1 or 2 DNS servers on each protcol. Ensure that
   the list of active DNS servers reflects the network configuration.
   In the case of overflow ensure that one protocol wins based on the
   first processed DHCP response.
 - On a network with intermittent IPv6 connectivity ensure that DNS
   resolution continues to function as DHCP and DHCPv6 updates are
   received.



    _______________________________________________________

File Attachments:


-------------------------------------------------------
Date: Thu 03 Oct 2019 12:05:06 PM UTC  Name:
0003-dhcp-dhcp6-Ensure-that-DHCP-DHCPv6-DNS-server-update.patch  Size: 4KiB  
By: davefiddes

<http://savannah.nongnu.org/patch/download.php?file_id=47612>

    _______________________________________________________

Reply to this item at:

  <https://savannah.nongnu.org/patch/?9858>

_______________________________________________
  Message sent via Savannah
  https://savannah.nongnu.org/