Many IBM i shops keep the SMTP server active on their system to support host-based applications that format and send e-mail messages such as alerts and notifications. With the SMTP server active your system could be open to spammers who could take over the SMTP server to relay their spam messages.
Check to see if SMTP is active:
WRKACTJOB SBS(QSYSWRK) JOB(QTSM*)
If there are any tasks displayed then the SMTP server is active.
Or check SMTP status in Nav: Network > Servers > TCP/IP Servers
Controlling SMTP mail relay involves two processes:
*ALL - open access, a very risky configuration
*NONE - deny all mail relays. Ff you are sending mail using SNDDST, SNDSMTPEMM or other program-controlled methods, you cannot leave this setting at *NONE as it will block mail being sent from your system
*LIST - only IP addresses that match an *ACCEPT SMTP list entry will be allowed or denied
*NEAR - only IP addresses that match a *NEAR SMTP list entry will be allowed
*BOTH - the system will look at both the *LIST and *NEAR entries
ADDSMTPLE TYPE(*ACCEPT) INTNETADR('10.100.1.2')
If you have been using SMTP list entries for a while, you may need to know what entries are already established. Examine the various members in the file named QATMADRLST in library QUSRSYS. Each member, which you will find appropriately named, contains the list entries for that type.
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