VCenter Server Appliance SSO Active Directory Sync Interval

On Red Hat systems, there's an /etc/mail/access file for sendmail.

And example of the contents is:

# Check the /usr/share/doc/sendmail/README.cf file for a description
# of the format of this file. (search for access_db in that file)
# The /usr/share/doc/sendmail/README.cf is part of the sendmail-doc
# package.
#
# by default we allow relaying from localhost...
Connect:localhost.localdomain           RELAY
Connect:localhost                       RELAY
Connect:127.0.0.1                       RELAY
172.16.2.116                            RELAY
172.16.2.17                             RELAY

You should define your vCenter's IP in that file (or its SuSE equivalent) and restart the daemon.

Edit:

I assumed you set Sendmail to listen on something other than its loopback address. Go into the sendmail.mc file and look for this stanza.

dnl # The following causes sendmail to only listen on the IPv4 loopback address
dnl # 127.0.0.1 and not on any other network devices. Remove the loopback
dnl # address restriction to accept email from the internet or intranet.
dnl #
DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl

You want to comment-out the last line there by adding dnl. So you should end up with:

dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl

Restart the sendmail service and try again.

Edit:

The OP is trying to configure their Linux-based vSphere appliance to relay through another mail server. This is just a case of defining a SMARTHOST. In your sendmail.mc file, find the line that says:

dnl define(`SMART_HOST', `smtp.your.provider')dnl

Remove the comment line and enter the name of your mail server. If your mail server's name is mail.bootylicious.com, your resulting sendmail.mc line will look like:

define(`SMART_HOST', `mail.bootylicious.com')dnl

Please make sure that you can ping the name you use...

Restart Sendmail.

Full disclosure: I'm not running vCenter. I have run other software packages with SQL Express, however.

You can run SQL Express maintenance jobs as scheduled tasks with batch and sqlcmd, like:

sqlcmd -E -SServer\instance -Q "EXECUTE [VIM_VCDB].[dbo].[cleanup_events_tasks_proc]"

Another article I found (http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1020904) suggested using a script which could be invoked like:

sqlcmd -E -SServer\instance -i "C:\Program Files\VMware\Infrastructure\VirtualCenter Server\cleanup_events_mssql.sql"

Edited in response to your edit: Limiting the size of your t-log can break really big transactions, including shrinks and large deletes. If VCenter itself rather than an Agent job is running the deletes, that could be your problem. And considering that the default is Express, it makes sense that they wouldn't depend on (unsupported in Express) agent jobs.