HA Access to Service during DR

[aclarke]

Eric,

I think you might benefit from some 1:1 architectural time with pre-sales.  I have arranged for your local team to contact you to give you a hand with some of the details of your design.

Cheers.

Aidan.

[ecornwell]

Great, any luck finding the doc?  I searched through the knowledge base and couldn't find anything.

We've got a pretty simple design.  Our Corp and DR networks are connected via a Layer 3 link.  In the event that the corp site is gone, all services will start at the DR site with the corp network.  Our VM infrastructure is setup with a network (vlan) for the corp network and SRM has a script that enables it.  I added an interface on our DR STM that exists in that vlan I just wasn't sure where to go from there.

[ecornwell]

Sounds good!  I'll make sure I post back with the results.

Thanks for all your help!

[owen · Accepted solution]

Documentation for libDNS.rts (the TrafficScript DNS library) has now been published here: libDNS.rts: Interrogating and managing DNS traffic in Stingray.

[ecornwell]

Awesome, thanks!

I've got one more question, I've got libDNS setup and I created a rule with the proper information as listed in HowTo: Implement a simple DNS resolver using libDNS.rts  The STM's now properly respond to DNS requests but it doesn't look like the GLB settings are taking effect.  I have GLB setup like Aidan linked to earlier in the post and its set for round robin for testing.  I turned on request tracing and it looks like the rule is taking effect prior to GLB doing anything.  Here's what I see:

0.001 ms		UDPReadClient (48 bytes)	Read UDP data from client
0.012 ms		RuleRun (HA-DNS)	Rule started
0.364 ms		RuleDiscard (HA-DNS)	Rule discarded the connection
0.380 ms		End	Request finished

The DNS Service is setup with GLB Enabled and has the pool set at Discard.  The HA-DNS rule was copied directly from the simple dns resolver and the domain and ips were the only thing changed.

I feel like I'm really close.  I thought I may have needed to add some glb stuff in the rule but it looks like most of the commands can only be used in a GLB service rule.

[ecornwell]

Any thoughts?

[aclarke]

Eric,

The library is designed to work as a loop back on another VS. You can't deploy it onto the same VS which is providing the GLB function. The GLB magic happens on the responses from the node, so if you respond from the TS library, GLB never gets a chance to do its thing.

Try chaining two VS's - do libDNS on VS2, and then make VS1 use VS2 as it's pool.  This should do the trick...

[ecornwell]

That makes sense, I was thinking to linearly.  Thank you for your help!!!  I'd give you 1000 pts if I could!

Edit: Got it working as expected!  Thanks for all your help!