F5 Public Cloud Solutions > Deploying F5 Solutions to GCP with Terraform and The F5 Automation Toolchain > F5 Application Services 3 Extension (AS3) Source | Edit on
Using AS3 to create services¶
Since your devices are now clustered in a sync-failover group and using auto-sync, you can post service declarations to whichever device you choose. A change to one BIG-IP will be automatically be replicated to the other.
In the previous steps in module 2 you validated that there were no virtual servers on the BIG-IPs. You can validate this again, but up until this point we have not modified the BIG-IPs to have any virtual servers.
Post AS3 declarations¶
Click on Lab4.3-AS3 under the drop down menu, select “as3.json” request. Right Click “Post as AS3 Declaration”.
Status code 200 response signals that Application Services 3 Extension (AS3) is completed on Big-IP 1.
AS3 and Service Discovery¶
As part of AS3, you can now leverage service discovery to automatically parse the cloud environment to look for Metadata. In GCP this is done via labels on instances, or items like forwarding rules. Review the Body of the declaration. The AS3 declaration is configured to discover pool members based on GCP labels.
Log into Big-IP1 => Local Traffic => Virtual Servers. Choose the “Example01” Partition from the Drop-down in the upper-right-hand corner. AS3 created two HTTP virtual servers: example01a and example01b.
Now within Big-IP1 => Local Traffic => Pools. Note “pool1”. AS3 used GCP tags to discover and auto-populate pool1 with two web servers.
Log into Big-IP2 => Local Traffic => Virtual Servers. Choose the “Example01” Partition from the Drop-down in the upper-right-hand corner. Even though you only POSTED an AS3 declaration to Big-IP1, Config Sync replicated the Virtual Servers and all supporting configuration objects (pools, profiles, etc.) to Big-IP2.