Already https://premium.wpmudev.org/forums/topic/i-can-not-enter-my-network-sites had mentioned that he could not enter directly into the sites of my network from my main site (perutic.com). The response indicated that I should remove domain mapping. Since I removed that plugin and multidomain, just does not work.
When I want to enter a subdomain administration this appears in the browser bar: http://lina.ed.pe/wp-login.php?redirect_to=http% 3A% 2F% 2Flina.ed.pe% 2Fwp-admin% 2F & reauth = 1. I can only see the contents of the site.