DC Migration

Telegram’s infrastructure is split across multiple Data Centers (DCs). When you connect to the wrong DC for your account, Telegram responds with a PHONE_MIGRATE_X or USER_MIGRATE_X error telling you which DC to use instead.

layer-client handles DC migration automatically and transparently. You don’t need to do anything.

How it works

1. You connect to DC2 (the default)
2. You log in with a phone number registered on DC1
3. Telegram returns PHONE_MIGRATE_1
4. layer-client reconnects to DC1, re-performs the DH handshake, and retries your request
5. Your code sees a successful response — the migration is invisible

The correct DC is then saved in the session file for future connections.

Overriding the initial DC

By default, layer-client starts on DC2. If you know your account is on a different DC, you can set the initial address:

#![allow(unused)]
fn main() {
use std::net::SocketAddr;

let client = Client::connect(Config {
    dc_addr: Some("149.154.167.91:443".parse::<SocketAddr>().unwrap()),
    ..Default::default()
}).await?;
}

DC addresses:

In practice, just leave dc_addr: None and let the auto-migration handle it.