[j-nsp] ipv4/ipv6-flow-table-size

[Scott Granados]

Here’s a bit more that I received that may help clear things up.


Scott,

A total of 4M flows can be created per 1 LU chip. Now it depends on the size that we allocate to ipv4-flow-table size,ipv6-flow-table-size and vpls-flow-table-size. 
If only ipv4 template is to be used, then all the memory on the pfe could be reserved only for the ipv4 family.

For eg:  if 15 is allocated for IPv4 then total flows that can be created = 15*256*1024 = 3932160 and 1k IPv6 flows and 1K vpls flows (default).
Each unit in flow hash table size corresponds to memory size of 256k (256x1024).

In your case, 
flow-table-size for ipv4 = 5, Total-flows that can be created = 5*256*1024 = 1310720
you are exporting @ 7k flows/sec to the flow-collector
If all of your traffic belongs to ipv4: Number of flows getting created = 7*1024*10 = 71680 flows/sec [ 10 = number of flow-records per 1 packet sent to flow-collector ]


On Aug 25, 2014, at 3:56 PM, Scott Harvanek <scott.harvanek at login.com> wrote:

> Scott,
> 
> Thanks, my next question then with that is - how/why is the default of 
> ipv4 15 and ipv6 1?  That would break that constraint of 15 total?
> 
> Scott H.
> Login Inc.
> 
> On 8/25/14, 3:53 PM, Scott Granados wrote:
>> When ever you set the flow table size you initiate a reboot of the FPC.  The table size is a combined value of v4 and v6 so 15 total a subset of which is IPV4 and the remainder is IPV6.
>> 
>> Thanks
>> Scott
>> 
>> On Aug 25, 2014, at 3:02 PM, Scott Harvanek <scott.harvanek at login.com> wrote:
>> 
>>> I'm wondering if anyone can clarify something for me from docs:
>>> 
>>> "
>>> 
>>>  * Any change in the configured size of flow hash table sizes initiates
>>>    an automatic reboot of the FPC.
>>>  * The total number of units used for both IPv4 and IPv6 cannot exceed 15.
>>> 
>>> "
>>> 
>>> - Does the initial config entry of ipv4/ipv6-flow-table-size cause the
>>> FPC to reboot or only if the configured value is changed?
>>> 
>>> -- I.e. the default for IPv4 size is 15, if that gets changed [ not
>>> currently set in config ] does that cause a reboot?
>>> 
>>> Also, is 15 the maximum aggregate or is it per table:
>>> 
>>> -- Can you have 15 units assigned to IPv4 and IPv6 at the same time? or,
>>> is 15 the maximum between the two?
>>> 
>>> Thanks!
>>> -SH
>>> 
>>> _______________________________________________
>>> juniper-nsp mailing list juniper-nsp at puck.nether.net
>>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>