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done_23947's avatar
done_23947
Icon for Nimbostratus rankNimbostratus
Jun 25, 2010

sending snmp request to same link

We just added a third ISP and I'm having trouble snmp polling the new router 12.239.13.1. It works only if request goes out new link (direct connection), but round robins to other two ISP's links and snmp doesn't respond. I would like to send request to this device though its direct connection only but can get iRule to stick it to one link. I have tried snatpool, IP::client_addr, IP::remote_addr, new pool w/ only one member(ATT_router) and pool member 12

 

 

when CLIENT_ACCEPTED {

 

if { [matchclass [IP::client_addr] equals $::facstaff_network]} {

 

snatpool snat_facstaff_network

 

**************************************************

 

} elseif { [matchclass [IP::remote_addr] equals $::alcatel_ATT_router] } {

 

pool ATT_router

 

forward

 

pool ISP_routers member 12.239.13.1

 

****************************************************

 

*

 

*

 

*

 

} elseif { [matchclass [IP::client_addr] equals $::neiu_dmz_subnets]} {

 

forward

 

pool ISP_routers member 64.107.163.1

 

} else {

 

return

 

}

 

}

 

application delivery
dev
devops
iRules

4 Replies

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  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Jun 26, 2010
    If it's monitor requests, the traffic will be sourced from the Linux host and not use a virtual server. Or are you trying to poll the new router through LTM from another host? If the former, you should be able to just configure a route for the router pointing out the correct VLAN. For load balanced connections, you could create the same route and then create a forwarding virtual server on the same IP address as the router with no iRule. By default with such a VS, LTM will not answer ARP for the IP, but will accept traffic for that IP and forward it according to the routing table.

     

     

    Aaron
  • Chris_Miller's avatar
    Chris_Miller
    Icon for Altostratus rankAltostratus
    Jun 28, 2010
    Does the poller have a private address? This should be a relatively easy iRule 

    when CLIENT_ACCEPTED { 
      if [IP::addr [IP::client_addr]] eq x.x.x.x { 
 snatpool y.y.y.y 
 pool z.z.z.z } }

    where x.x.x.x is the IP of the poller, y.y.y.y is the snatpool containing a snat on the 12.239.13.1 network (or maybe use automap if you have a selfip there), and z.z.z.z is a pool that only contains the router 12.239.13.1.
  • done_23947's avatar
    done_23947
    Icon for Nimbostratus rankNimbostratus
    Jun 29, 2010
    Thanks, I believe it is working.

     

     

    Question. I notice when replacing one iRule w/ another it will take multiple iRule. Can I simple add another iRule (example above rule) and leave current rule in-place? Is this common?

     

  • Chris_Miller's avatar
    Chris_Miller
    Icon for Altostratus rankAltostratus
    Jun 29, 2010
    Posted By done on 06/29/2010 01:42 PM

     

    Thanks, I believe it is working.

     

     

    Question. I notice when replacing one iRule w/ another it will take multiple iRule. Can I simple add another iRule (example above rule) and leave current rule in-place? Is this common?

     

     

     

    You can indeed stack rules - people have differing opinions on whether you should. I typically like to because it can simplify each individual rule but this does cause some confusion about the order of events. Here's a good read: http://devcentral.f5.com/Tutorials/TechTips/tabid/63/articleType/ArticleView/articleId/240/Stacking-iRules-A-Modular-Approach.aspx