ClusterBlockException after upgrade 1.7 to 2.1


I upgraded my cluster from 1.7 to 2.1. Everything was green with the migration plugin.
Some of my indices where set as read only.
After the upgrade ALL my indices are not readable. I got a ClusterBlockException when a do a basic _search request. Indices are OPEN.

Here is the config of the cluster and a index:

The only solution i have is to re-index everything but it's HUGE!

Any idea to solve this ?

Please post the full error message. Is the cluster still green?

I retrieved the full message

{"error":{"root_cause":[{"type":"cluster_block_exception","reason":"blocked by: [FORBIDDEN/5/index read (api)];"}],"type":"cluster_block_exception","reason":"blocked by: [FORBIDDEN/5/index read (api)];"},"status":403}

Looks like the index is read only. You don't have index.blocks.read_only set to true in the index settings have you?

I posted my index cluster settings and in both there is :

"blocks": {
"read_only": "false"

But, even if the index is considered "read-only", it should be readable. In my case, i can't query (_search) on it