This topic describes how to update the configuration of a running service mesh.
Modifying the Egress Traffic Mode
The egress traffic mode defines a policy for the external access to services in the mesh. Two options are available: Registry Only (access to only services automatically discovered by the mesh and manually registered services is allowed) and Allow Any (access to any address is allowed).
Steps for configuring the egress traffic mode for the mesh are as follows:
2. On the mesh basic information page, click the Edit button of the Egress traffic mode field to pop up the Modify Egress traffic mode window.
3. Select Allow Any or Registry Only as required, and click Confirm to complete the update of the egress traffic mode.
Enabling HTTP 1.0 Support
Istio does not support HTTP 1.0 by default. When necessary, you need to enable HTTP 1.0 support on the mesh basic information page:
Disabling HTTP Auto Retries
Istio automatically retries failed HTTP requests twice by default. If this does not meet your requirements, you can disable auto retries on the mesh basic information page:
Disabling auto retries applies to the entire mesh. However, you can still set explicit retry policies for specific virtual services.
Enabling DNS Proxy
Istio sidecars support DNS proxy. When DNS proxy is enabled, DNS traffic will also be blocked, and DNS requests will be responded directly by sidecars. On the one hand, sidecars cache DNS resources, which will accelerate DNS responses. On the other hand, in the case of cross-cluster service access in multi-cluster mesh scenarios, the service can still be parsed properly without the need to create a service with the same name in the client cluster. You may follow the steps below to enable DNS forwarding:
2. On the basic information page, click on the right of DNS Proxying > DNS forwarding to enable DNS forwarding. See the figure below:
To automatically allocate IP addresses for ServiceEntrys with no address defined, enable auto IP allocation. For more information, see Address auto allocation.