> I changed pop3server port to 1555 (greater than 1024) -> still able to > send messages > to the James server (by seeing it process emails) == message retrieval > is still OK? > 1) Does it matter which value I give to pop3server's port? How is the > port used > for message retrieval?
POP3 by default is looked for and found on 110, anything else has to be specified by users in their account settings. > I changed smtp server port to 2500, and start sendmail so that sendmail > can listen to port 25 again. -> can not send messages to the James > server anymore. (no email processing when I try send emails to it) You need to tell sendmail to connect to James on 2500, and no external mail transport agent (MTA) will be able to contact James. > 2) So how can I still receive messages in James when its smtp port is > configured something other than 25. You can't really do this unless you can re-configure *every* MTA that will connect to James. That limits this scenario to local networks, or only approved users. > > Because I just want to run not as root. Unfortunatly this is a fact of life, SMTP uses port 25, ports < 1024 can only be opened by root. > > 3)Some simple question: > When James is not up, and someprocess tries to send emails to it. > When James is back up, it is able to handle these emails. SMTP doesn't provide any mechanism for caching mail, in practice SMTP MTA's will generally re-try a message a few times over some period (every hour for 72 hrs for example) providing *very* limited failsafe behaviour. > How can it do > it, using pop3server or smtp server...? > SMT = sending/receiving emails ??? SMTP is used to transport mail from one MTA to another. Mail clients insert mail into the transport using SMTP too. Some clients can recieve mail using SMTP. > POP3 = retrieving emails ??? POP3 is a protocol used to access a repository of mail, mail clients use POP3 to retrieve mail from a server. POP3 is best suited to clients which can be offline for significant periods, control of mail retrieval is by the client. SMTP is really only suitable for permanent connections, there is a real danger of losing mail if an MTA is subject to extended time offline. IMAP is a sophisticated server based repository for mail, mail in an IMAP server stays on the server, making it most appropriate where a user may move about, but is always on-line for mail. d. -- To unsubscribe, e-mail: <mailto:james-user-unsubscribe@;jakarta.apache.org> For additional commands, e-mail: <mailto:james-user-help@;jakarta.apache.org>
