Re: IBM i Access for Web vs IBM Navigator for i

Yes, V6 and V7 are the same operationally.

As to if turning off IPV6 will improve iNav performance, it depends on if the workstations are trying to use IPV6 to communicate or not. I suspect not. I'm guessing that root cause lies elsewhere, most likely in memory allocation to the host servers, DNS speed, etc.

Jim Oberholtzer
Chief Technical Architect
Agile Technology Architects


On 11/4/2013 10:07 AM, Steinmetz, Paul wrote:

A few questions about the IPV6 issue.
Is this the same on V6R1 and V7R1?
I'm currently on V6R1, not using IPV6, however, the below message posts following IPL or system saves.
TCP8A2A - Start IPv6 request completed successfully.
Even though IPV6 is started successfully, is it correct that turning off IPV6 may improve iNAV performance?

Thanks
Paul

-----Original Message-----
From:midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Gqcy
Sent: Monday, November 04, 2013 10:49 AM
To:midrange-l@xxxxxxxxxxxx
Subject: Re: IBM i Access for Web vs IBM Navigator for i

Is there a way to turn off IPV6 while TCP is active, or do I need to ENDTCP and start it again?


On 11/4/2013 9:21 AM, Dan Kimmel wrote:

> More than just CPU cycles: I'm not sure of all the mechanics, but there's a timeout wait for an IPV6 DNS server to respond before it'll kick down to IPV4. That timeout is repeated, and repeated, and repeated on every access to a server, even if the IP address is given in IPV4 notation.
>
> Java always "prefers" IPV6 unless you tell it otherwise on the java command line. The product I develop for RJS is a java web-app that talks to a java web-service, both running on i. Our customers started installing 7.1 (where the default for starting IPV6 changed) and performance on our product fell through the floor for some customers even though they had moved to a faster machine. The solution turned out to be either to turn off IPV6, or to add the -preferIPV4=true flag on the java command line, or to configure IPV6 properly.
>

>> -----Original Message-----
>> From:midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-
>> bounces@xxxxxxxxxxxx] On Behalf Of Jim Oberholtzer
>> Sent: Monday, November 04, 2013 7:21 AM
>> To: Midrange Systems Technical Discussion
>> Subject: Re: IBM i Access for Web vs IBM Navigator for i
>>
>> Nevertheless, it's a reasonable question. If there is an attempt to
>> communicate with IPV6, then significant CPU cycles may be expended to
>> detect and communicate with the network. It's best to turn off IPV6
>> unless it is properly configured and in use. Remember the defaults are
>> on, not off.
>>
>> Jim Oberholtzer
>> Chief Technical Architect
>> Agile Technology Architects
>>
>>
>> On 11/3/2013 5:45 PM, Jack Callahan wrote:

>>>> Do all these systems have IPV6 configured properly? This sounds a lot like

>>>>> that problem. You don't notice it when all the IP you're doing is telnet or
>>>>> FTP, but when you start to use highly interactive web interfaces, like
>>>>> WebNav, missing IPV6 DNS server definitions KILL performance.
>>>>>

>>> A bit presumptive of IBM to assume IPv6 is in use, if that's the cause of
>>> the performance problem.
>>>
>>> Haven't run across anywhere in IBM documentation the states IPv6 is the
>>> preferred networking protocol for Navigator for i.
>>>
>>> IPv6 certainly isn't in use on my firm's networks- still running IPv4
>>> everywhere. And yet other web apps seem to run acceptably.
>>> --

>> --