# How to fix ERR_SSL_VERSION_OR_CIPHER_MISMATCH

**Published by:** [bap2pecs](https://paragraph.com/@0xb2p/)
**Published on:** 2024-02-06
**URL:** https://paragraph.com/@0xb2p/how-to-fix-err-ssl-version-or-cipher-mismatch

## Content

I was setting up SSL for a domain using cloudflare along with nginx-acme and nginx-proxy but I got error ERR_SSL_VERSION_OR_CIPHER_MISMATCH when testing. Checking the container logs, everything looks alright. By using SSL Labs toolkit, it shows error “Failed to communicate with the secure server”: Looking it up, I found https://community.cloudflare.com/t/failed-to-communicate-with-the-secure-server/186871 which links to https://developers.cloudflare.com/ssl/troubleshooting/version-cipher-mismatch Then I found the root cause was I was using a multi-level subdomain: One easy way to fix it is to merge the multiple levels from <subdomain1>.<subdomain2> to <subdomain1>-<subdomain2>. But sometimes we do need multi-level subdomains. For example, when we deploy L2s for our clients. We want them to get resource URLs such as: https://myappchain.rpc.snapcha.in https://myappchain.explorer.snapcha.in … In that case, we will use Cloudflare’s Advanced Certificates add-on feature that covers more than one level of subdomain. One we purchased the package, we need to order those advanced certificates such as: Then we can use the feature to issue certs when it becomes active:

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