#12654 HIGH Not Tri: Unexpected IP address change

[Zarro Boogs per Child]

#12654: Unexpected IP address change
--------------------------------+-------------------------------------------
           Reporter:  wad       |       Owner:  shep         
               Type:  defect    |      Status:  new          
           Priority:  high      |   Milestone:  Not Triaged  
          Component:  wireless  |     Version:  not specified
         Resolution:            |    Keywords:  XO-4 WLAN    
        Next_action:  diagnose  |    Verified:  0            
Deployment_affected:            |   Blockedby:               
           Blocking:            |  
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Comment(by rsmith):

 The log file wad attached is very informative.  Note this is at his home
 not at twine so a different DHCP server.

 We start:

 {{{
 Apr 12 16:47:08 xo-93-20-c1 dhclient[2226]: DHCPREQUEST on eth0 to
 255.255.255.255 port 67 (xid=0x3b4ff9c1)
 Apr 12 16:47:09 xo-93-20-c1 dhclient[2226]: DHCPACK from 172.24.0.1
 (xid=0x3b4ff9c1)
 Apr 12 16:47:09 xo-93-20-c1 dhclient[2226]: bound to 172.24.0.238 --
 renewal in 1565 seconds.
 Apr 12 16:47:09 xo-93-20-c1 NetworkManager[420]: <info> (eth0): DHCPv4
 state changed bound -> renew
 Apr 12 16:47:09 xo-93-20-c1 NetworkManager[420]: <info>   address
 172.24.0.238
 }}}

 Renewal is scheduled to happen in 26 minutes.
 But 26 minutes later there isn't any renewal.  The next bit of traffic
 isn't until almost an hour later when NetworkManager decides that things
 have expired and it does a DISCOVER rather than a renew.

 {{{
 Apr 12 17:52:25 xo-93-20-c1 kernel: [ 4107.904288] Restarting tasks ...
 done.
 Apr 12 17:52:37 xo-93-20-c1 NetworkManager[420]: <info> (eth0): DHCPv4
 state changed renew -> expire
 Apr 12 17:52:37 xo-93-20-c1 kernel: [ 4119.995778] PM: Syncing filesystems
 ... done.
 Apr 12 17:52:37 xo-93-20-c1 dhclient[2226]: DHCPDISCOVER on eth0 to
 255.255.255.255 port 67 interval 8 (xid=0x53541964)
 Apr 12 17:52:37 xo-93-20-c1 NetworkManager[420]: <info> (eth0): DHCPv4
 state changed expire -> preinit
 }}}

 So the bug here appears to be time related.  A 2nd problem is that the
 DISCOVER seems to happen while the interface is configured with an IP.
 Someone should ask about this behavior as it seems that its almost
 guaranteed to make servers give you a new IP since the RFC has the ping
 check marked as SHOULD. Its on by default in both ISC and dnsmasq.

-- 
Ticket URL: <http://dev.laptop.org/ticket/12654#comment:18>
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