Changing the setting to random and the fork value to 40 gives me a 
reasonable chance that all 40 forks will be more or less equally 
distributed.  With more than 40 blades, it's a good bet only one fork per 
blade.  Of course, being random, I could someday get all 40 forks going to 
one blade.  It's not that the blade is already at 100% CPU,  it's that 
hitting a single blade with 40 updates at the same time will not only 
flatline my cpu, but the ethernet sockets for the same blade as well.  And 
on some of my blades, the system may try and move LPARs to different blades 
to re-equalize the load, which just then makes it take even longer.

This is a semi-common option, at least in the network scanning tools I have 
used.  I was hoping it would already be here and I just wasn't seeing it.

For instance,

 Nmap 6.47SVN ( http://nmap.org )
 Usage: nmap [Scan Type(s)] [Options] {target specification}
 TARGET SPECIFICATION:
   -iR <num hosts>: Choose random targets


And for Nessus
  http://static.tenable.com/documentation/nessus_5.0_user_guide.pdf  page 11

 Avoid Sequential Scans  

 By default, Nessus scans a list of IP addresses in sequential order. If 
checked, Nessus
 will scan the list of hosts in a random order. This is typically useful in 
helping to
 distribute the network traffic directed at a particular subnet during 
large scans


  
We have to be careful when we scan our Z series boxes for instance with 
Nessus.  Thank goodness for random host selection.

This is a scalability issue as far as I am concerned.

>>>Ericw

On Sunday, October 5, 2014 2:23:20 PM UTC-4, Michael DeHaan wrote:
>
> There's no such setting.
>
> However, I don't understand why changing the order wouldn't smakc your 
> *other* blade, so this question seems orthogonal. 
>
> Sounds like you need to take it out of rotation if it's already nearing 
> 100% CPU, such as using our load balancing modules.
>
>
>
> On Sun, Oct 5, 2014 at 1:24 PM, Eric Wedaa <[email protected] 
> <javascript:>> wrote:
>
>> How do I shuffle/randomize long lists of hosts?  That is, without writing 
>> an executable hosts file that randomizes them and then spits them out, and 
>> then dealing with all the groupings and variables and other wonderfulness 
>> that I can include in the hosts file?
>>
>> My inventory file is collected semi-dynamically and comprises long lists 
>> of servers that are all running on the same blade on a long list of 
>> blades.  I run upto 40 servers per blade, and I have about a 80 blades (or 
>> more).  The FIRST time I run an "update bash" (for instance) I'll wind up 
>> hitting all of one blade first, effectively flat-lineing it.  If I can 
>> shuffle my hosts list, I can have a larger fork/serial value and won't  
>> flatline my blades and I can shorten my effective runtime.
>>
>> I was hoping for a "--shuffle-hosts" variable but I couldn't find it.
>>
>> >>>Ericw
>>
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