mabl Link 3.0 is a new version of the secure tunnel between the mabl cloud and your private environments. Link Agents connect faster than before, recover from network interruptions on their own, and hold up under heavy test load. You can also share one tunnel across your whole company, route a run through your own computer, decide who can reach a tunnel, and check a connection from the Desktop App or the mabl CLI. Link 3.0 replaces the legacy Link service, which shuts down on March 15, 2027.
Link 3.0 highlights
- A faster, more resilient tunnel - The Link Agent connects over QUIC on UDP port 443 when it can reach mabl directly, and over a secure WebSocket on TCP port 443 when it goes through an HTTP proxy. Both use fixed endpoints instead of a host name generated for each agent, and your firewall needs to allow only one of them. See Link Agent requirements.
- Tunnels for your company, and for you - A company-scoped tunnel serves every workspace in your company from one set of Link Agents, and takes precedence over a workspace tunnel with the same name, so you can move workspaces onto it without editing an environment. A personal Link tunnel routes your own cloud runs through your computer, so you can test a local build with full cloud results before it is deployed anywhere.
- Control over who reaches your tunnels - Choose which roles can reach your private services from the Desktop App and the CLI, and whether mabl support can reach them while helping you troubleshoot. See Controlling access to Link tunnels.
- Training and diagnostics over Link - Train tests over a Link tunnel in the Desktop App, and check a tunnel's connectivity from the Desktop App or the CLI before a run depends on it.
- Easier to install, run, and watch - A Windows installer and a Linux and macOS installer set the agent up as a service, or you can run one from the mabl CLI with no Java required. Maintenance mode drains an agent before you take its host offline, updates install beside the running version so you can roll back, and Settings > Networking shows throughput, latency, and host health for every agent. See Monitoring Link Agents and tunnels.
Other changes in Link 3.0
Along with the above highlights, Link 3.0 brings other changes that matter when you size a host or set up a new agent.
- Sizing - Each tunnel runs as its own process, so plan host memory by the number of tunnels. See Sizing and scaling Link Agents.
- Proxy settings - A Link Agent with no proxy settings of its own now follows its host's proxy configuration, including a PAC script.
- Java - Java 11 is the minimum for archive installations. The installers and the mabl CLI bring their own runtime.
- Company API keys - A company API key can now be of type "Link Agent", which is how you create a company-scoped tunnel.
Migrating from legacy Link to Link 3.0 lists everything that carries over and everything that changes.
Migrating to Link 3.0
Link 3.0 is turned on per account. Once your Link Agents run version 3.0 and your firewall allows the new endpoints, contact mabl to switch your account over. Until then, agents on version 3.0 keep using the legacy tunnel, and nothing about your runs changes.
Legacy Link shuts down on March 15, 2027, and Link Agents that haven't moved to 3.0 stop working on that date. For who is affected and what to do, see Legacy mabl Link ends March 15, 2027.
The process of migrating to Link 3.0 depends on how your Link Agents are installed:
- An agent installed from the zip or tar.bz2 download on Settings > Networking picks up Link 3.0 when you restart it, as long as automatic updates are on. An agent with automatic updates turned off needs a manual upgrade.
- Docker and Kubernetes agents need the
mablhq/link-agent:3image, ormablhq/link-agent:3-ubuntuon arm64 hosts. - Windows agents can move to the new installer.
Once your agents are running on version 3.0 or later, you'll need to make sure each host allows outgoing connections to the Link 3.0 tunnel endpoints and contact mabl to turn on Link 3.0 for your account.
For the full process, including how to confirm every agent is connected before your cloud runs move over, see Migrating from legacy Link to Link 3.0. If you have questions about the migration or need help planning it, contact mabl.