Hi I have dovecot-2.36.4 (director +5 nodes) - backend to auth is openldap+keepalived to second ldap

For test i shutdown my ldap server - keepalive  works perfectly VIP switched - ldapserach works ok (all connect to second ldap) but I noticed strange dovecot behavior - some user get "no response" or "waiting waiting"

in dovecot i use: auth_cache_negative_ttl = 5 mins auth_cache_size = 20 M auth_cache_ttl = 5 mins

service lmtp { inet_listener lmtp { address = 127.0.0.1 10.0.100.4 port = 24 } process_min_avail = 5

protocol lmtp { auth_socket_path = director-userdb mail_plugins = quota expire notify mail_log passdb { args = proxy=y nopassword=y port=24 driver = static name = } syslog_facility = local3 }

in ldap server i have: idletimeout     256

Any idea ?