Does app-to-app traffic stay in our 3tera-hosted grid's LAN?

[David Crane]

I should be able to get this answer from traceroute, but it is reporting "* * *" for each probe, which probably means they are timing out due to something related to our hosting environment (3tera provides hosting, so I do not have direct access to the xen layers).

Our AppLogic 2.1.1 installation is using 3 separate apps. The "www" app connects to the "data" and "search" apps, where our relational database and search engines reside. The connections from "www" go out through a NET component and arrive in "data" or "search" through IN components. The connections are done through hostnames that are DNS resolved to IP addresses in the IP block assigned to our grid.

Recently I've begun measuring the Mbps used by our production components and realized that passing "data" and "search" traffic through so many components was wasteful. Then I thought to verify whether the app-to-app hops seemed to be routed through the LAN at the border router. That's when I got stumped by traceroute.

[PavelGeorgiev]

David,

If you are using the gateway appliances, then the traffic is passing through the external network. This does not necessarily means it hits the wire - if the two gateway appliances are running on the same physical server traffic will never leave the server.

Hope that helps,
Pavel

[PeterNic]

David,

Traffic between components of the same application pass on the grid backbone. The backbone bandwidth is not metered.

Traffic between apps passes through the front network. If the apps are on the same grid, the traffic between them should not be metered either. The border router should not be involved here unless the gateway subnets are configured incorrectly -- you should see wirespeed L2 traffic. If you see something different, please contact support.

The IN/OUT/NET components are responsible for filtering traffic and ensuring secure communications. They also allow you to break up your application and run it on multiple different systems. Their firewalls may be what is preventing traceroute from getting too deep.

Best regards,
- Peter