Project

General

Profile

Feature #201

Change default DHCP Lease time to 4 hours or greater

Added by charlesghopkins about 12 years ago. Updated over 11 years ago.

Status:
Closed
Priority:
Medium
Assignee:
Category:
setup-storage
Target version:
-
Start date:
05/20/2009
Due date:
% Done:

50%

Estimated time:
1.00 h

Description

The lease renewal is a factor especially because you have a device that is filling / servicing a a LOT of roles and if you can minimize the impact ..... When you are gaming you do not want a lease renewal in the middle especially if someone is streaming media from the HDA and due to bandwidth cannot get a DHCP address.

"Lease duration is another area to consider (i.e. the amount of time before a client needs to renew its DHCP address) - if this is set too long, and there are a large number of mobile clients, there is a risk of running out of available IP addresses as these mobile clients join the network, lease an address and then leave again without releasing it; conversely, too short and there is a large amount of renewal traffic as the DHCP client attempts to renew its lease at the half life. For most environments, I find that an 80:20 rule can be applied - i.e. provide 20% more addresses than are expected to be in use at any one time (to cater for mobile clients) and set the lease time to 1 day but for a subnet with largely static PCs, then longer leases may be appropriate."

Recommended settings:
4 hours = 240 <---- I would recommend not going below this minimum.
8 hours = 480
12 hours = 720 <--- This setting would be optimal, I think, for a home environment.
24 hours = 1440
8 days = 11520 (default recommended time for the specification).

http://www.imconf.net/imc-2007/papers/imc17.pdf

http://www.markwilson.co.uk/blog/2005/07/best-practices-for-managing-automatic.htm

http://www.google.com/search?q=dhcp+lease+time+best+practice

imc17.pdf - UsageBased DHCP Lease Time Optimization PDF (359 KB) charlesghopkins, 05/20/2009 06:55 PM

History

#1 Updated by charlesghopkins about 12 years ago

#2 Updated by pjcrux about 12 years ago

charlesghopkins wrote:

The lease renewal is a factor especially because you have a device that is filling / servicing a a LOT of roles and if you can minimize the impact ..... When you are gaming you do not want a lease renewal in the middle especially if someone is streaming media from the HDA and due to bandwidth cannot get a DHCP address.

"Lease duration is another area to consider (i.e. the amount of time before a client needs to renew its DHCP address) - if this is set too long, and there are a large number of mobile clients, there is a risk of running out of available IP addresses as these mobile clients join the network, lease an address and then leave again without releasing it; conversely, too short and there is a large amount of renewal traffic as the DHCP client attempts to renew its lease at the half life. For most environments, I find that an 80:20 rule can be applied - i.e. provide 20% more addresses than are expected to be in use at any one time (to cater for mobile clients) and set the lease time to 1 day but for a subnet with largely static PCs, then longer leases may be appropriate."

Recommended settings:
4 hours = 240 <---- I would recommend not going below this minimum.
8 hours = 480
12 hours = 720 <--- This setting would be optimal, I think, for a home environment.
24 hours = 1440
8 days = 11520 (default recommended time for the specification).

http://www.imconf.net/imc-2007/papers/imc17.pdf

http://www.markwilson.co.uk/blog/2005/07/best-practices-for-managing-automatic.htm

http://www.google.com/search?q=dhcp+lease+time+best+practice

hdactl needs to read an external file for the value of the DHCP Lease. That way it is more easily managed by users without mucking with the master script. -Chaz|home

#3 Updated by essary about 12 years ago

  • Status changed from New to Closed

#4 Updated by cpg almost 12 years ago

  • Status changed from Closed to Assigned
  • Assignee set to cpg
  • % Done changed from 0 to 50

reopening it as we have a patch for the platform to do this.

we are also changing the default per the recommendation above. Thanks, charlesghopkins.

also thanks to Essary (aka mr orange) for some of the patch.

the other half, the daemon, needs to be done to finish this off.

#5 Updated by cpg over 11 years ago

  • Status changed from Assigned to Closed

fixed and released in amahi 5.0!

Also available in: Atom