→ Applies to: SynetoOS 4.x

Symptom

The client reported not receiving any email notifications.

The sender's email hostname could not be resolved by sendmail (does not exist).

Solution

Step 1. Connect to SynetoOS appliance via SSH as admin

ssh admin@<your_ip_address_or_hostname>

Step 2. Check logs

less /var/log/messages

EXAMPLE OUTPUT

Nov 25 09:45:04 syneto-os-produzione-domain sendmail[29475]: 2AP8j482029475: ruleset=check_mail, arg1=<no-reply@syneto-os-produzione.domain.local>, relay=root@localhost, reject=553 5.1.8 <no-reply@syneto-os-produzione.domain.local>... Domain of sender address no-reply@syneto-os-produzione.domain.local does not exist

Step 3. Open hosts file

vi /etc/hosts

Step 4. Fix the incorrect domain (replace <synetoos_hostname> and <domain_name> with the correct information)

::1 syneto-os-produzione syneto-os-produzione.sinterfiltri.local localhost loghost
127.0.0.1 syneto-os-produzione <synetoos_hostname>.<domain_name> localhost loghost
#-- LocalHypervisor
172.16.254.1 syneto-esxi-345ab876
#-- End
#-- VMware
192.168.26.199 syneto-esxi-b7613c07-192.168.26.199
192.168.26.200 esxi-192.168.26.200
192.168.26.230 esxiSyneto.sinterfiltri.local-192.168.26.230
172.16.254.1 esxiSyneto.sinterfiltri.local-172.16.254.1
#-- End