OS: CentoOS 7.1 IPA: 4.1.0-18 SSSD: 1.12.2-58 With IPA any clients running CentOS7.1 authentication for ssh and sudo takes more than 5 seconds _after_ putting in password. If ssh to the IPA server itself, it authenticates instantly. Google did not provide much relevant information. Note that this is not a slow ssh session to get to authentication prompt, it always gets to the prompt without delay. Also it is not related to NFS performance, it is equally slow if I login to a NFS server (IPA client) locally or login to a server (also a IPA client) that has autofs home. IPA server is a fresh installation with just a couple of users. I had an installation previously that has more than a thousand user accounts on CentOS 6. Users did not have the slowness problem as with this new installation. Hope this list can provide some pointers. Thanks in advance. Qing Chang