No inbound traffic to external firewall interfaces in Azure and change to default NSG behaviour (2024)

FAQs

What port is configured by default to allow all traffic through the NSG? ›

The AllowInternetOutbound default security rule in both NSG1 and NSG2 allows the traffic unless you create a security rule that denies port 80 outbound to the internet. If NSG2 denies port 80 in its security rule, it denies the traffic, and NSG1 never evaluates it.

Unlike Azure Firewall, which monitors all traffic for workloads, NSG is commonly deployed for individual vNets, subnets, and network interfaces for virtual machines to refine traffic. It does so by activating a rule (allow or deny) or Access Control List (ACL), which allows or denies traffic to Azure resources.

You can use an Azure network security group to filter network traffic between Azure resources in an Azure virtual network. A network security group contains security rules that allow or deny inbound network traffic to, or outbound network traffic from, several types of Azure resources.

Azure Firewall provides inbound protection for non-HTTP/S protocols (for example, RDP, SSH, FTP), outbound network-level protection for all ports and protocols, and application-level protection for outbound HTTP/S.

When initially deployed, a set of default rules is assigned to the NSG, allowing all incoming and outgoing traffic across the Azure Virtual Network and all outgoing traffic to the internet. Note that you cannot delete these rules, but you can set new rules with a higher priority to supersede them.

If a subnet has no security group associated to, all network traffic is allowed through it. You can filter network traffic between subnets using Network security groups.

Inbound and outbound network traffic on a subnet is controlled using a network security group. To control inbound traffic, create network security rules in a network security group. Then assign the network security group the subnet containing the App Service Environment.

You can use a network security group to filter inbound and outbound network traffic to and from Azure resources in an Azure virtual network. Network security groups contain security rules that filter network traffic by IP address, port, and protocol.

To allow your server in the subnet to access the internet through the Azure Firewall, you need to configure a network rule on the Azure Firewall. In the Azure Firewall settings, go to Rules and then select Network rule collection. Click on Add network rule collection.

In the Azure portal, open your firewall resource group and select the firewall. Under Monitoring, select Diagnostic settings. For Azure Firewall, three service-specific legacy logs are available: Azure Firewall Application Rule (Legacy Azure Diagnostics)

What are the three types of rules in an Azure firewall? ›

You can configure NAT rules, network rules, and applications rules on Azure Firewall using either classic rules or Firewall Policy.

Secure outbound addresses with a firewall that can control outbound traffic based on FQDNs. Azure Firewall restricts outbound traffic based on the FQDN of the destination or FQDN tags.

Agents connect to port 17778 on the SolarWinds Platform server or Additional Polling Engine by default.

If the port number is omitted, Ncat uses its default port 31337. Typically only privileged (root) users may bind to a port number lower than 1024. A listening TCP server normally accepts only one connection and will exit after the client disconnects.

Clients may be configured to use the default 8080 port on your Traffic Server host as a proxy.

The default SSH port is 22.