selecting the one mxbw.bluewin.ch with highest priority and sending a email in manual mode using telnet connection to port 25 of mxbw.bluewin.ch.
from: email@example.com to: firstname.lastname@example.org (our mailbox at bluewin mail service) [root@webservices log]# telnet mxbw.bluewin.ch 25 Trying 18.104.22.168... Connected to mxbw.bluewin.ch (22.214.171.124). Escape character is '^]'. 220 zhhdzmsp-mxin30.bluewin.ch ESMTP Service (Swisscom Schweiz AG) ready helo eer 250 zhhdzmsp-mxin30 says HELO to 126.96.36.199:46758 mail from: email@example.com 250 MAIL FROM accepted rcpt to: firstname.lastname@example.org 250 RCPT TO accepted data 354 continue. finished with "\r\n.\r\n" asd;fgkljsdfg;lksdfjg adsg;flkdjsfg;sdlfkgj ad;flgkjsdf;glksdfjg . 250 <C1/27-03568-96BD1035@zhhdzmsp-mxin30.bluewin.ch> Mail accepted quit 221 zhhdzmsp-mxin30 closing connection Connection closed by foreign host. as you see, message was accepted (and we really received it to our mailbox email@example.com)
now sending from eergeneve.ch server (IP 188.8.131.52) using the same way root@eer:/var/log/exim4# ifconfig eth1 eth1 Link encap:Ethernet HWaddr 54:04:a6:68:0c:ba inet addr:184.108.40.206 Bcast:220.127.116.11 Mask:255.255.255.240 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:102905636 errors:0 dropped:0 overruns:0 frame:0 TX packets:107634860 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:13499925625 (12.5 GiB) TX bytes:117991720597 (109.8 GiB) Interrupt:17 Memory:fbde0000-fbe00000
root@eer:/var/log/exim4# telnet mxbw.bluewin.ch 25 Trying 18.104.22.168... Connected to mxbw.bluewin.ch. Escape character is '^]'. 220 zhbdzmsp-mxin21.bluewin.ch ESMTP Service (Swisscom Schweiz AG) ready helo eer 250 zhbdzmsp-mxin21 says HELO to 22.214.171.124:46818 mail from: firstname.lastname@example.org 250 MAIL FROM accepted rcpt to: email@example.com 250 RCPT TO accepted data 354 continue. finished with "\r\n.\r\n" this is a test message . 554 FROM: <eer> (126.96.36.199) Not spooled, transaction failed. quit 221 zhbdzmsp-mxin21 closing connection Connection closed by foreign host. as you see, message hasn't been accepted (and we received delivery failure notification to firstname.lastname@example.org)
We changed config of our server to pass fqdn-like name with helo and it works well.
Too strange to have such mandatory condition, but in general that's not a problem. 😉
About sending email from different servers. You're right. It's the same server but different IPs. Our first IP was 188.8.131.52, but we changed it recently to find out what is the cause of mail rejection from bluewin (we assumed blacklisted IP or subnet). Now it's 184.108.40.206 (the same subnet of our IP-pool). But anyway we have SPF record configured, so different IPs isn't a problem if recipient supports SPF check. And BTW a question, do your mail servers support SPF check?