The firewall broke everything
Spoke 1 can't reach the API in Spoke 2.
- Get Spoke 1 reaching the API on vm-api (443) through azfw-hub
- Keep SSH from Spoke 1 to vm-api blockedbroken
- Don't peer the spokes to each otherbroken
Background
"Since the new firewall went in last night, Spoke 1 can't reach the API in Spoke 2." The API runs on vm-api on 443, and vm-spoke1 calls it. The plan: all spoke-to-spoke traffic goes through azfw-hub, an Azure Firewall at 10.0.1.4. HTTPS from Spoke 1 to Spoke 2 is allowed, everything else between the spokes is blocked, and the spokes are never peered to each other.
- 1See it fail
Prove the problem yourself before you change anything. Reports are often wrong.
VM commands forVMsssh vm-spoke1What's this?
Opens a shell on vm-spoke1, so the next commands run on that VM. In this lab it's a shortcut. In real Azure you'd connect through something like Azure Bastion, or SSH to an address you can reach.
nc -zv 10.2.1.4 443What's this?
netcat, a standard Linux tool. Tries to open a TCP connection and reports whether it worked.
-zonly check whether the port answers. Send no data-vprint the result in words10.2.1.4where to connect443the port to try
Ticks off when the test runs on vm-spoke1.
- 2Find where it stops
- 3Name the cause
- 4Fix it and test again
?
- Resource group, the outer dashed frame
- Virtual network, with its address space top right
- Subnet, with range and usable IPs (5 reserved)
- Network security group. A small shield on a VM's NIC means the NIC has one too
- Route table on the subnet
- VM Appliance Private endpoint
- Peering Connected Initiated or access off
- Goal working Goal broken, X marks where it stops
- Private DNS zone, dotted lines go to linked VNets
- Orange pulse: what your last command changed. Drag to pan, Ctrl and scroll to zoom.
vm-spoke1 → vm-api:443should work: not workingvm-spoke1 → vm-api:22should stay blocked: blocked