multiple nozzles on firehose


Nix, Lon <Lon.Nix@...>
 

I'm trying to get an idea of how multiple instances of the firehose-to-syslog app nozzle will interact

Does the firehose act like a queue in the sense that once a nozzle reads a message its gone from the hose and if there are multiple nozzles will only one nozzle will read each message at a time? For example, if the messages in the firehose are A, B, C, and D and two nozzles alternate then the first nozzle will read A and C and the 2nd nozzle will read B and D. If either nozzle goes down while reading a message then that message will be lost, but then that nozzle won't take any more messages.

Thanks,

--Lon Nix


Rohit Kumar
 

Hi Lon,

The traffic controller takes a subscription ID as a parameter whenever a
firehose connection is made. If you use the same subscription ID on each
nozzle instance, the firehose will evenly distribute events across all
instances of the nozzle. For example, if you have two nozzles with the same
subscription ID, then half the events will go to one nozzle and half to the
other. Similarly if there were three instances of the nozzle, then each
instance would get one-third the traffic.

Does that help?

Thanks,
Rohit

On Mon, Nov 9, 2015 at 9:39 AM, Nix, Lon <Lon.Nix(a)schwab.com> wrote:

I'm trying to get an idea of how multiple instances of the
firehose-to-syslog app nozzle will interact



Does the firehose act like a queue in the sense that once a nozzle reads a
message its gone from the hose and if there are multiple nozzles will only
one nozzle will read each message at a time? For example, if the messages
in the firehose are A, B, C, and D and two nozzles alternate then the first
nozzle will read A and C and the 2nd nozzle will read B and D. If either
nozzle goes down while reading a message then that message will be lost,
but then that nozzle won’t take any more messages.



Thanks,



--Lon Nix



Nix, Lon <Lon.Nix@...>
 

That answers my question, thanks!

Out of curiosity, what happens if nozzles with different subscription IDs subscribe to the same firehose?

--Lon Nix


Rohit Kumar
 

Both of the nozzles will get all the events coming from the firehose.

On Tue, Nov 10, 2015 at 4:51 PM, Nix, Lon <Lon.Nix(a)schwab.com> wrote:

That answers my question, thanks!



Out of curiosity, what happens if nozzles with different subscription IDs
subscribe to the same firehose?



--Lon Nix