On 12 September 2017 at 17:59, John Beranek wrote:
On 11 September 2017 at 14:28, Jakub Hrozek wrote:
On Mon, Sep 11, 2017 at 12:23:26PM +0100, John Beranek wrote:
On 1 September 2017 at 15:54, Lukas Slebodnik wrote:
On (01/09/17 09:33), William Edsall wrote:
Had a few communications with Michal but we're still stuck.
One issue is that we have dozens of domain controllers globally. A standard dns lookup could give me a domain controller overseas which will be slow, or maybe even a domain controller that isn't responding. As such, I have been inserting ad_server = x into the sssd.conf to improve performance.
I noticed that if I do not insert ad_server = x, I'm getting different results. My initial id request is very slow but seems to produce results. While searching, it seems to also be 'inserting' users into the users hash table - almost as if it's searching and inserting our entire user database? For example there are countless lines of the following: (Fri Sep 1 09:28:37 2017) [sssd[be[example.com]]] [sdap_nested_group_hash_insert] (0x4000): Inserting [CN=user_name,OU=bla,OU=bla Users,DC=dow,DC=com] into hash table [users]
As my initial id request returns, it seems to return several chunks of my group ids at once as if it's processing them individually and searching all users in that group (thus the above log entries).
Not sure if this helps or just muds up the issue but it's strange indeed.
You needn't hardcode ad_server. You can still rely on dns discovery. I assume you use sites in AD. So you can "pin" sssd to your local/nearest site with option ad_site.
I've got something to add to this, some behaviour we're seeing with CentOS 7 servers using sssd-ad.
sssd-1.14.0-43.el7_3.18.x86_64 sssd-ad-1.14.0-43.el7_3.18.x86_64 sssd-client-1.14.0-43.el7_3.18.x86_64 sssd-common-1.14.0-43.el7_3.18.x86_64 sssd-common-pac-1.14.0-43.el7_3.18.x86_64 sssd-ipa-1.14.0-43.el7_3.18.x86_64 sssd-krb5-1.14.0-43.el7_3.18.x86_64 sssd-krb5-common-1.14.0-43.el7_3.18.x86_64 sssd-ldap-1.14.0-43.el7_3.18.x86_64 sssd-proxy-1.14.0-43.el7_3.18.x86_64
In our case we have some DCs which are located at a partner site, and are therefore inaccessible to clients on our standard LANs.
When SSSD starts it will correctly determine there are 2 primary DCs (these are the ones for the site) and 7 backup DCs.
However, what is happening from time to time is that for some reason I've not yet determined the connection(s) to the primary DC(s) are dropping, and then sssd attempts to connect to one of the DCs that are inaccessible.
In what circumstances would sssd prefer a backup server to a primary server?
I've got a chunk of log which I've anonymised:
https://paste.fedoraproject.org/paste/G69lC9COQfbnWFI~qtFLZw
The issue is here:
[snip]
So this is a known bug where locating the site (even though we know it already) can contact the DCs outside that site.
In the meantime, until the fix is released, you can hardcode the site using the 'ad_site' option.
Thank you Jakub, is there a ticket/BZ for this? I noticed after my post that it's evident on CentOS 6 too.
Ah, https://pagure.io/SSSD/sssd/issue/3265 ?
John