[Samba] RPC Server Unavailable - Error

[Anantha Raghava]

Hi,

We were running Samba-AD - Version 4.7.6 for over 2 years without any 
errors. We have 4 Domain Controllers in our setup and DNS is BIND_DLZ 
(BIND 9.9.4). Off late (since 8th June 2019) we upgraded the Samba-AD 
version to 4.10.4 and all of sudden we started receiving the error "RPC 
Server not available" when we are trying to join the new PCs to domain. 
After multiple attempts the PC gets added to domain. We restart samba 
server on the log on server, the error goes off. There is no specific 
pattern for this appear to appear.

We are receiving the same error whenever we are trying to add a new user 
or modify a user attribute in RSAT. When this error comes, we have to 
restart the RSAT server multiple times to start functioning again.

Is there is any specific reason for this error? How do we fix it.

My smb.conf is as shown below.

--------------------------------------------------------------------------------------------------

Global parameters
[global]
         netbios name = PDC
         realm = EXZA.COM
         server role = active directory domain controller
         workgroup = EXZA
         server services = s3fs, rpc, nbt, wrepl, ldap, cldap, kdc, 
drepl, winbindd, ntp_signd, kcc, dnsupdate
         idmap_ldb:use rfc2307 = yes
         ldap server require strong auth = No
         dns forwarder = 192.168.100.1
# Logs and events
         eventlog list = Security
         log level = 3
         log file = /var/log/samba/pdc.%T.log
         max log size = 1000000
[sysvol]
         path = /usr/local/samba/var/locks/sysvol
         read only = No
[netlogon]
         path = /usr/local/samba/var/locks/sysvol/exza.com/scripts
         read only = No

--------------------------------------------------------------------------------------------------
Thanks & regards,

Anantha Raghava

eXzaTech Consulting And Services Pvt. Ltd.

Ph: +91-9538849179, E-mail: raghav at exzatechconsulting.com 
<mailto:raghav at exzatechconsulting.com>

URL: http://www.exzatechconsulting.com <http://www.exzatechconsulting.com/>


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