[arm-allstar] load balancing

[Patrick Perdue]

Hi:

We are attempting to debug a setup that (mostly) follows the howto at 
HamVoIP for load balancing for a single public node, which also has a 
repeater directly attached to it. Not my setup, but if it were, I'd have 
the connections and repeater on separate Pi's. Anyway, the node is 
running on a Pi 4, and audio gets very choppy when the connection count 
reaches about 85 or so during a popular net, so we want to try load 
balancing to hopefully clean that up.

Seems there are some errors in the examples in that document, a few 
cases of missing closing brackets and the like.

https://www.hamvoip.org/howto/limiting_connections_and_balancing.pdf

Once corrected, we now see this in the log.


    -- Executing [51018 at blacklist:1] 
NoOp("IAX2/123.123.123.123:4569-131", "57512") in new stack
     -- Executing [51018 at blacklist:2] 
GotoIf("IAX2/123.123.123.123:4569-131", "0?blocked") in new stack
     -- Executing [51018 at blacklist:3] 
Goto("IAX2/123.123.123.123:4569-131", "radio-secure|51018|1") in new stack
     -- Goto (radio-secure,51018,1)
     -- Executing [51018 at radio-secure:1] 
NoOp("IAX2/123.123.123.123:4569-131", "Date: 02/05/2023") in new stack
     -- Executing [51018 at radio-secure:2] 
NoOp("IAX2/123.123.123.123:4569-131", "Incoming node: 57512") in new stack
     -- Executing [51018 at radio-secure:3] 
Set("IAX2/123.123.123.123:4569-131", "i0=") in new stack
     -- Executing [51018 at radio-secure:4] 
Set("IAX2/123.123.123.123:4569-131", "i1=") in new stack
     -- Executing [51018 at radio-secure:5] 
Set("IAX2/123.123.123.123:4569-131", "i2=") in new stack
     -- Executing [51018 at radio-secure:6] 
Set("IAX2/123.123.123.123:4569-131", "i3=") in new stack
[Feb  5 14:57:57] WARNING[6577]: ast_expr2.fl:407 ast_yyerror: 
ast_yyerror():  syntax error: syntax error, unexpected '+', expecting 
$end; Input:
  +  +  +
  ^
[Feb  5 14:57:57] WARNING[6577]: ast_expr2.fl:411 ast_yyerror: If you 
have questions, please refer to doc/channelvariables.txt in the asterisk 
source.
     -- Executing [51018 at radio-secure:7] 
Set("IAX2/123.123.123.123:4569-131", "Total=") in new stack
[Feb  5 14:57:57] WARNING[6577]: ast_expr2.fl:407 ast_yyerror: 
ast_yyerror():  syntax error: syntax error, unexpected '<', expecting 
$end; Input:
  < 204
  ^
[Feb  5 14:57:57] WARNING[6577]: ast_expr2.fl:411 ast_yyerror: If you 
have questions, please refer to doc/channelvariables.txt in the asterisk 
source.
     -- Executing [51018 at radio-secure:8] 
GotoIf("IAX2/123.123.123.123:4569-131", "?51018|100:51018|30") in new stack
     -- Goto (radio-secure,51018,30)
     -- Executing [51018 at radio-secure:30] 
NoOp("IAX2/123.123.123.123:4569-131", "Too many connections to node 
51018!") in new stack
[Feb  5 14:57:57] WARNING[6577]: pbx.c:1832 pbx_extension_helper: No 
application '168505|X' for extension (radio-secure, 51018, 31)
   == Spawn extension (radio-secure, 51018, 31) exited non-zero on 
'IAX2/123.123.123.123:4569-131'
     -- Hungup 'IAX2/123.123.123.123:4569-131'

I think possibly what is happening is that a variable is null, and it 
breaks when it tried to add null to null. Could be wrong though.

Here is the relevant part of the dialplan.


[radio-secure]

exten => 51018,1,NoOp(Date: ${STRFTIME(${EPOCH},,%m/%d/%Y)})
exten => 51018,n,NoOp(Incoming node: ${CALLERID(number)})
exten => 51018,n,Set(i0=${GLOBAL(LINKS1)})
exten => 51018,n,Set(i1=${GLOBAL(LINKS2)})
exten => 51018,n,Set(i2=${GLOBAL(LINKS3)})
exten => 51018,n,Set(i3=${GLOBAL(LINKS4)})

;;; Calculate total connections.
exten => 51018,n,Set(Total=$[${i0} + ${i1} + ${i2} + ${i3}])
;;; Compare total to 204 (200 plus 4 local virtual nodes)
exten => 51018,n,GotoIf($[${total} < 204]?51018,100:51018,30)

exten => 51018,30,NoOp(Too many connections to node 51018!)
exten => 51018,n,168505|X
Nodes 168500 through 168505 are defined in a custom file, which is 
referenced in rpt.conf with the relevant events as documented in the PDF.


So... what is breaking things here?

Thanks and 73

N2DYI