still seeing some delays in lookups

Re: still seeing some delays in lookups

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Another fix I saw listed was to use the forwarders option. So that all
non-locally & non-cached lookups are done by another server. Since I'm
downstream of Sprint, I would assume I could point to their DNS servers
as my forwarder.

Is that correct that it will only use the forwarder for non-local &
non-cached lookups?

Also, apparently to another post I saw, Apple had not been notified of
this issue. The person spoke with an Apple Technician who said they
were unaware of it, and now had opened a (I want to say ticket, but
can't remember what he called it) so that are looking at the problem.
Plus, A fix would be issued in 9.3.1.

On Nov 15, 2004, at 3:06 PM, Men & Mice Support wrote:

> Sorry, I made a mistake. After conferring with our developers, it has
> been made clear to me that the only way to disable EDNS is to use a
> configuration option that is not fully compatible with QuickDNS.
>
> Edit the file /var/named/conf/options. Add this option into the
> options block:
>
> edns-udp-size 512;
>
> Save the file and tell named to reconfig:
>
> rndc -k /var/named/conf/user_before reconfig
>
> However, if you later change any server options (in the server's
> Options window), QuickDNS Remote (not recognizing this option) will
> remove it again.
>
> Chris Buxton
> Men & Mice - Making DNS Easy
> Customer Service and Sales Engineer
>
> At 3:02 PM -0800 11/12/04, Patrick Windmiller wrote:
>> I'd like the instructions for compiling it my self, with that option
>> disabled.
>>
>>
>> On 11/12/04 2:54 PM, "Men & Mice Support" <cbuxton@menandmice.com>
>> wrote:
>>
>>> It's possible that the EDNS (extended DNS) packet size is an issue.
>>> Unfortunately, the ends-udp-size option is not yet compatible with
>>> QuickDNS, because QuickDNS Remote won't recognize it and will have a
>>> problem.
>>>
>>> BIND 9.3.0 can be compiled without this feature. We can create a
>>> compiled version like that for anyone who'd like to try it and
>>> report
>>> back whether it helps.
>>>
>>> The issue here is that, before EDNS, UDP packets in DNS use were
>>> limited to 512 bytes. This is because, historically, the UDP
>>> transport layer was limited to 512 bytes per packet. EDNS allows a
>>> sort of negotiation between two DNS servers to determine optimal
>>> packet size (i.e. the largest size of packet that will arrive intact
>>> at the other end). These limits are now being expanded.
>>>
>>> With EDNS, the servers at either end can negotiate a larger maximum
>>> packet size. Unfortunately, this takes a little time. Fortunately,
>>> the information can be cached.
>>>
>>> Chris Buxton
>>> Men & Mice - Making DNS Easy
>>> Customer Service and Sales Engineer
>>>
>>> At 2:37 PM -0800 11/12/04, Jody McAlister wrote:
>>>> The mac os x server list had a "fix" which goes one step beyond the
>>>> fix that was given here. I still see a lookup issue, less than
>>>> before (but I am using firefox and Safari which everybody seem to
>>>> say have that problem currently), but the lookups still seem a
>>>> little slower than what I'm used to as well.
>>>>
>>>> Here is an email I pasted in about making an adjustment to the udp
>>>> packet that they claim solved their problem. Does this seem like a
>>>> solution or just an unneccessary extra step. I don't see that he
>>>> tried with bind 9.3.0 before changing the packet size.
>>>>
>>>> ******************************************************************
>>>> Hello everyone,
>>>>
>>>> Thanks for the replies from all. It does seem the DNS timeout
>>>> issue I
>>>> mentioned this morning isn't OS X Server related. In fact, it
>>>> seems to be
>>>> some type of bug involving BSD, IPv6 and Bind 9.2.x... Apparently
>>>> some of
>>>> the root servers started issuing IPv6 replies in the past few weeks
>>>> causing the issue to crop up. There is a good discussion in this
>>>> thread
>>>> here:
>>>>
>>>> http://discussions.info.apple.com/webx?
>>>> 14@123.Votva3t2BDi.0@.689de754/0
>>>>
>>>> While not a "proper" solution, my solution to this problem was to
>>>> compile
>>>> Bind 9.3.0 on our XServe. I renamed the old named binary and put
>>>> the new
>>>> one in its place. Also, I edited the system startup script so it
>>>> launches
>>>> bind -4 (IPv4 support ONLY) instead of just bind. Lastly, I
>>>> changed the
>>>> edns-udp-size to limit the packet size to 512 bytes. All of these
>>>> together have solved this issue, at least in our environment.
>>>>
>>>> I encourage anyone experiencing the original symptoms to check out
>>>> the
>>>> discussion linked above and try out the fix I did.
>>>>
>>>> Thanks everyone
>>>> Mike
>>>
>>>
>
>
>
Jody McAlister
President
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