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SES with a EC2 installed Direct Admin cPanel, Email issue,

0

I am trying to connect Direct Admin with EC2, For some reason emails are receiving yet not delivering, Domain verified, LImit has been increased Already,

Looking at the direct admin end I get this error, can someone help me to figure this out, please,,this is what i get from direct admin support team,

your server cannot connect to that host. That part is not related to directadmin. Your server cannot connect to the amazon specified host via tcp 25 port.

Here's one of their IP addresses:

root@server:/etc# telnet 54.163.229.159 25
Trying 54.163.229.159...


Tcpdump:
root@server:/home/ubuntu# tcpdump host 54.163.229.159
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes

12:18:05.105550 IP server.mysite.net.43454 > ec2-53-160-339-149.compute-1.amazonaws.com.smtp: Flags [S], seq 2048819245, win 62727, options [mss 8961,sackOK,TS val 3288246009 ecr 0,nop,wscale 7], length 0

12:18:06.131103 IP server.mysite.net.43454 > ec2-53-160-339-149.compute-1.amazonaws.com.smtp: Flags [S], seq 2048819245, win 62727, options [mss 8961,sackOK,TS val 3288247035 ecr 0,nop,wscale 7], length 0

12:18:08.147070 IP server.mysite.net.43454 > ec2-53-160-339-149.compute-1.amazonaws.com.smtp: Flags [S], seq 2048819245, win 62727, options [mss 8961,sackOK,TS val 3288249051 ecr 0,nop,wscale 7], length 0

12:18:12.275057 IP server.mysite.net.43454 > ec2-53-160-339-149.compute-1.amazonaws.com.smtp: Flags [S], seq 2048819245, win 62727, options [mss 8961,sackOK,TS val 3288253179 ecr 0,nop,wscale 7], length 0

12:18:20.467067 IP server.mysite.net.43454 > ec2-53-160-339-149.compute-1.amazonaws.com.smtp: Flags [S], seq 2048819245, win 62727, options [mss 8961,sackOK,TS val 3288261371 ecr 0,nop,wscale 7], length 0

12:18:36.595058 IP server.mysite.net.43454 > ec2-53-160-339-149.compute-1.amazonaws.com.smtp: Flags [S], seq 2048819245, win 62727, options [mss 8961,sackOK,TS val 3288277499 ecr 0,nop,wscale 7], length 0

Try to open tcp 25 out explicitly or so

Topics
ComputeFront-End Web & MobileBusiness Applications
Tags
Website HostingAmazon EC2Amazon Simple Email Service
Language
English
Jayanga
asked 4 months ago158 views
1 Answer
0

is the outbound connection on port 25 being initiated from an EC2 instance? Outbound port 25 on EC2 instances is blocked by default to try and prevent spamming. You can request for the port to be opened, the steps are here https://repost.aws/knowledge-center/ec2-port-25-throttle

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EXPERT
Steve_M
answered 4 months ago
  • Jayanga
    4 months ago

    No, I have already double checked this.even the AWS Support, they also verified that the port block have lifted.had use the same link and did this already

  • Steve_M EXPERT
    4 months ago

    Thanks, good to know.

    The tcpdump output in the question is a bit garbled, could you edit the question so that it's enclosed in the code tag please? Either select the text and click </> or else put three backticks before the first line of output, and the same after the last line.

    Can you also help to understand the hosts involved here - there's server (in your shell prompt), and 54.163.229.159, and ec2-53-160-339-149 (which doesn't make sense, as the third octet > 255).

    What host does what, and what works, and what doesn't?

    Thanks.

  • Steve_M EXPERT
    4 months ago

    Which hosts are involved here? And which is a source(es) and which is a target(s) of the traffic on port 25?

    As it looks like Ubuntu is being used, check whether the Ubuntu firewall ufw is in use, and if it is then ensure port 25 is open.

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