There is no single best SNI for VLESS Reality that works for everyone. On Iran-related networks, start by checking that serverName, public key, short ID, flow, destination behavior, and client core version match the private endpoint. Random SNI changes often break Reality verification and hide the real routing or DNS issue.
Why SNI is the wrong first question
Most failed VLESS Reality setups are not fixed by guessing another SNI. Reality checks several fields at once: serverName, public key, short ID, flow, destination behavior, and the server-side config. If one field is stale, copied wrong, or unsupported by the client core, the connection can fail even when the SNI looks fine.
That matters for people searching from Iran. Queries like "best SNI for VLESS Reality Iran" show up because the error message mentions Reality or TLS. What actually helps is a validation workflow, not a public list of hostnames.
SNI checklist before you change anything
- Confirm serverName: It must match the endpoint design, not a random domain from a public post.
- Confirm public key and short ID: One stale character is enough to fail Reality verification.
- Confirm flow: Clients handle xudp, vision, and legacy flow values differently.
- Update the client core: Old xray-core builds can fail on configs that work elsewhere.
- Compare networks: Test mobile data and Wi-Fi separately before blaming SNI.
When changing SNI is reasonable
Change SNI only when the endpoint owner documents an alternate serverName, or when you control both client and server config. If you do not control the endpoint, ask for the current share link or full field list instead of editing SNI on your own.
If a managed provider supplies the VLESS endpoint, treat their share link as the source of truth. Import it fresh, then test DNS and exit IP. Do not mix fields from old screenshots, Telegram posts, or different client exports.
Better diagnostic signals than SNI
Write down the exact error string, client name, client version, network type, DNS mode, and whether the failure changes between Wi-Fi and mobile data. "Reality verification failed" usually points to key, short ID, clock, or serverName mismatch. "TLS handshake timeout" more often means reachability, MTU, IPv6, DNS interception, or blocked destination behavior.
If you need a private endpoint
For stable VLESS/Xray access, use a private managed endpoint rather than public free configs. Proxy Poland plans include VLESS/Xray, OpenVPN, HTTP, and SOCKS5 on dedicated Polish mobile proxy infrastructure with private credentials and support.