# E2B 2.59.0 adds DNS server control for sandbox network access

published: 2026-10-22T17:05:31.631Z
topic: infrastructure
source: https://github.com/e2b-dev/E2B/releases/tag/e2b%402.59.0
url: https://aiagentnews.io/stories/e2b-2-59-0-adds-dns-server-control-for-sandbox-network-access

E2B has released version 2.59.0 of its e2b package, adding a DNS server setting to sandbox network options. The release also deprecates the API and sandbox URL connection options.

The new dnsServers network option, exposed as dns_servers in Python, sets which DNS servers a sandbox can reach when its allowOut list includes a domain. If the option is left out, the default of 8.8.8.8 applies, a list of IP addresses allows only those servers, and an empty list allows none. According to the release, the setting only opens the firewall and does not change the sandbox's /etc/resolv.conf.

updateNetwork and update_network reset the DNS servers to the default when the field is omitted, like the other fields, while getInfo and get_info report the value when one is set. Separately, the apiUrl and api_url and sandboxUrl and sandbox_url options, along with the E2B_API_URL and E2B_SANDBOX_URL environment variables, are now deprecated. They still work for now and will be removed in the next major version.

Sandbox traffic on e2b-tango.dev, e2b-juliett.dev and foxtrot-2.e2b.dev now uses the unified https://sandbox. endpoint.

## Why it matters if you build agents

Agents that reach external domains can now limit which DNS servers a sandbox may query instead of relying on the 8.8.8.8 default, and an empty list blocks all DNS servers. Code that sets apiUrl, sandboxUrl or their environment variables should move off them before the next major version removes them. Teams that hardcode sandbox hostnames should check their configuration against the three domains listed.