Ok I think I have figured out what I did wrong, I had not set up elasticsearch to restart automatically, so everytime it shut down this would happen
We have 3 magento installation on our server: production, test enviroment and m4.3 which use elastic search.
On our production store we use mysql catalog search (not elastic) but problem exist. After we change one product category by editing product, all catalog disapear until reindex is done.
Is it possible that problems comes from elastic if we see this problem in store which do not use elasticsearch???