I have a posting in Experts Exchange on this matter also, but I am trying here to see if I can get some kind of response. I had to rebuild a new RH Linux Sendmail Server 8.0 because ours unfortunately died. The hard drive was dying and it would not mount the /usr partition. Anyways, I temporarily setup a W2K3 SMTP server just to keep e-mail going while I built a new RH Linux Server 8.0 with sendmail. I installed and configured Sendmail and I am able to send/receive e-mail with no problems. I made the installation and put into our network on 5/10. Just starting last Thursday we had a users tying to send an email with attachment to @hanger.com. And received the following:
The original message was received at Thu, 15 Jun 2006 11:51:09 -0700
from mvo-randy.scope.local [192.168.5.8]
----- Transcript of session follows -----
451 4.4.1 reply: read error from hanger.com.inbound10.mxlogic.net.
451 4.4.1 reply: read error from hanger.com.inbound10.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound20.mxlogic.net.
451 4.4.1 reply: read error from hanger.com.inbound20.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound30.mxlogic.net.
451 4.4.1 reply: read error from hanger.com.inbound30.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound40.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound40.mxlogic.net.
<cfaborlando@hanger.com>... Deferred
Warning: message still undelivered after 4 hours
Will keep trying until message is 5 days old
So at this point I was starting to monitor my MQUEUE, and I started to troubleshoot with this address. I can send email with no problems, in fact I was even able to send a 5KB attachment. But as soon as I would send anything higher than 7KB it would get deleayed and it get stuck in my queue. Now sendmail.org states that this is known issue with this version and to try to use SMTP rather than ESMTP. At first, I thought it was the ESMTP protocol because in my maillog I see VERIFY=FAIL so indicating it did not authenticate with each other. Of course it would not make this communication because we do not have each others certificates. But that is what I thought was the problem. But I see the same thing when I just send a regular email with no attachment and that one goes through! So made sendmail make an SMTP connection to this SMTP address and still the message would get stuck in the MQUEUE. If I had a misconfiguration in Sendmail wouldn't I have an issue sending to ALL SMTP's rather than a selective few. I do not believe it is a network issue since I can receive attachments from these STMP's with no problems, and I do not have issues with other SMTP’s: Yahoo, Hotmail, Sharp.com, CDW.com and many others... I did not have an issue at all with the Microsoft W2K3 SMTP server neither. With the W2K3 Server I am able to send these attacments to @hanger.com with now problems. I am clueless on this problem as of now I am downloading RH 9.0 to see if this helps any. If anyone has any suggestions or has seen this please let me know!
P.
The original message was received at Thu, 15 Jun 2006 11:51:09 -0700
from mvo-randy.scope.local [192.168.5.8]
----- Transcript of session follows -----
451 4.4.1 reply: read error from hanger.com.inbound10.mxlogic.net.
451 4.4.1 reply: read error from hanger.com.inbound10.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound20.mxlogic.net.
451 4.4.1 reply: read error from hanger.com.inbound20.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound30.mxlogic.net.
451 4.4.1 reply: read error from hanger.com.inbound30.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound40.mxlogicmx.net.
451 4.4.1 reply: read error from hanger.com.inbound40.mxlogic.net.
<cfaborlando@hanger.com>... Deferred
Warning: message still undelivered after 4 hours
Will keep trying until message is 5 days old
So at this point I was starting to monitor my MQUEUE, and I started to troubleshoot with this address. I can send email with no problems, in fact I was even able to send a 5KB attachment. But as soon as I would send anything higher than 7KB it would get deleayed and it get stuck in my queue. Now sendmail.org states that this is known issue with this version and to try to use SMTP rather than ESMTP. At first, I thought it was the ESMTP protocol because in my maillog I see VERIFY=FAIL so indicating it did not authenticate with each other. Of course it would not make this communication because we do not have each others certificates. But that is what I thought was the problem. But I see the same thing when I just send a regular email with no attachment and that one goes through! So made sendmail make an SMTP connection to this SMTP address and still the message would get stuck in the MQUEUE. If I had a misconfiguration in Sendmail wouldn't I have an issue sending to ALL SMTP's rather than a selective few. I do not believe it is a network issue since I can receive attachments from these STMP's with no problems, and I do not have issues with other SMTP’s: Yahoo, Hotmail, Sharp.com, CDW.com and many others... I did not have an issue at all with the Microsoft W2K3 SMTP server neither. With the W2K3 Server I am able to send these attacments to @hanger.com with now problems. I am clueless on this problem as of now I am downloading RH 9.0 to see if this helps any. If anyone has any suggestions or has seen this please let me know!
P.