vnet peering det disconnected when changing a backend pool in app gw

[ghost]

This issue was originally opened by @neidiom as hashicorp/terraform#18091. It was migrated here as a result of the provider split. The original body of the issue is below.

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I paired two vnets. One is where my Application Gateway is. Everytime I change something, like adding a new ip to the backend pool, the vnet peering breaks. Here is the error message.

* azurerm_virtual_network_peering.vnet_peer_2_ned_app_gw_vnet: 1 error(s) occurred:

* azurerm_virtual_network_peering.vnet_peer_2_xxx_app_gw_vnet: Error Creating/Updating Virtual Network Peering "peer_xxx_app_gw_vnet_to_xxx_xxx_vnet" (Network "xxxxs-vnet-12345" / Resource Group "xx-xx-west-test-xxxx-application-gateway-rg"): network.VirtualNetworkPeeringsClient#CreateOrUpdate: Failure sending request: StatusCode=400 -- Original Error: Code="RemotePeeringIsDisconnected" Message="Cannot create or update peering /subscriptions/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx/resourceGroups/xx-xx-west-test-xxxx-application-gateway-rg/providers/Microsoft.Network/virtualNetworks/xxxxs-vnet-12345/virtualNetworkPeerings/peer_xxx_app_gw_vnet_to_xxx_xxx_vnet because remote peering /subscriptions/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx/resourceGroups/xx-xx-netrg/providers/Microsoft.Network/virtualNetworks/xx-xx-vnet/virtualNetworkPeerings/peer_xxx_xxx_vnet_to_xxx_app_gw_vnet referencing parent virtual network /subscriptions/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx/resourceGroups/xx-xx-west-test-xxxx-application-gateway-rg/providers/Microsoft.Network/virtualNetworks/xxxxs-vnet-12345 is in Disconnected state. Update or re-create the remote peering to get it back to Initiated state. Peering gets Disconnected when remote vnet or remote peering is deleted and re-created." Details=[]

[tombuildsstuff]

hey @neidiom

Thanks for opening this issue :)

Just to let you know that we're holding off doing any improvements to the Application Gateway resource until this bug is resolved - since it's making it extremely challenging to test fixes work as expected (since, there's about an 80% failure rate deleting Application Gateways at the moment). Once that issue's been resolved we can look into scheduling some time to investigate issues with the Appliation.

Thanks!

[tombuildsstuff]

hi @neidiom

Given this issue is blocked on an upstream issue in the Azure API rather than keeping multiple issues open and trying to ensure they all remain up to date - I'm going to close this in favour of #1576 which is the Meta-Issue tracking the Bugs and Enhancements for the Application Gateway Resource. Once the bug in the API is fixed we should be able to take a look into this, but we'll keep track of the status of this issue there for the moment.

Thanks!

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. If you feel I made an error 🤖 🙉 , please reach out to my human friends 👉 hashibot-feedback@hashicorp.com. Thanks!