Yep. Get it on the same network as the server and run the command: telnet 192.168.10.1 25

You *should* get a welcome banner from Postfix. If you do, type "QUIT" to exit cleanly - this means the problem is almost certainly with the router. If you don't, and based on your previous reply to Mike Wright I suspect that is going to be the case, then you most likely need to either look at FirewallD again or possibly SELinux. The latter *should* have been sorted out automatically, but just in case, you can temporarily disable SELinux with the command: sudo setenforce 0 To reenable it, use the command: sudo setenforce 1 On 9 April 2015 at 20:54, Peter Ulrich Kruppa <pukruppa(a)googlemail.com&gt; wrote: > > > Am 09.04.2015 um 20:52 schrieb Andy Blanchard: >> >> Hi Peter, >> >> 0.0.0.0 is a "wildcard"; Postfix is definitely running and listening >> for incoming connections on port 25 on any IP address on your server. >> >> Do you have access to another PC or something on your internal network >> that you can try connecting from? At least that way you could >> determine whether you need to focus on the router or the server - >> although based on your updates on FirewallD and Postfix, I'm leaning >> more towards either the router or your ISP blocking SMTP by default at >> present. > > Hi Andy, > > I have some old laptop running debian. Can I do something with it - without > setting up another mail server on it? :-) > > >> >> On the latter point, it might be worth looking at their FAQ or maybe >> contacting support just in case; some ISPs block SMTP by default as an >> anti-spam measure but will open it up on request, but others require >> you have some form of "premium" connection to host your own servers. >> >> Andy >> >> On 9 April 2015 at 19:16, Peter Ulrich Kruppa <pukruppa(a)googlemail.com&gt; >> wrote: >>> >>> Am 09.04.2015 um 19:05 schrieb Rick Stevens: >>>> >>>> >>>> On 04/09/2015 07:22 AM, Peter Ulrich Kruppa wrote: >>>>> >>>>> >>>>> Am 09.04.2015 um 15:32 schrieb Robert Nichols: >>>>>> >>>>>> >>>>>> On 04/09/2015 05:07 AM, Peter Ulrich Kruppa wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> I set up a Postfix-Server on my Fedora 21 box, which is connected to >>>>>>> the internet via >>>>>>> some Netgear Router. My private LAN is 192.168.10.0/24 with the >>>>>>> Fedora >>>>>>> box fixed on >>>>>>> 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, >>>>>>> let's >>>>>>> say for >>>>>>> mydomain.com . >>>>>>> >>>>>>> Now I can >>>>>>> - send myself mails from my Fedora box >>>>>>> - send mails from my Fedora box to the outside p. ex. my >>>>>>> googlemail >>>>>>> account >>>>>>> >>>>>>> but I can't receive mails from outside. >>>>>> >>>>>> >>>>>> >>>>>> The default postfix configuration has it listening only on the >>>>>> localhost >>>>>> interface. You will have to change that. Look for "inet_interfaces >>>>>> =" >>>>>> in /etc/postfix/main.cf . >>>>> >>>>> >>>>> I have got >>>>> inet_interfaces = all >>>>> in there. >>>> >>>> >>>> >>>> Many ISPs block SMTP traffic TO their end users. Most also block >>>> outgoing SMTP traffic FROM their end users _unless_ it's going to the >>>> ISP's mail servers (this is to prevent end users from becoming spam >>>> farms). Assuming your ISP permits bi-directional SMTP traffic, here >>>> are things to look at: >>> >>> >>> It does - I had that working using a DSL bridge (modem) instead of a >>> router. >>> >>>> 1. The outside world must send mail to the PUBLIC IP of your firewall >>>> (not the 192.168.x.y address, but the one that's on the public >>>> Internet). Make sure your MX DNS records reflect that public IP address. >>>> If your MX records contain "192.168.x.y" or "10.x.y.z", then your record >>>> is wrong (192.168.0.0/16 and 10.0.0.0/8 are non-routable, private >>>> networks). >>>> >>>> 2. You must configure your external firewall to forward incoming port >>>> 25 traffic to port 25 on your postfix machine's PRIVATE IP address. >>>> >>>> 3. Make sure firewalld on your postfix machine permits incoming port 25 >>>> traffic. >>> >>> >>> Points 1. to 3. should be allright - hopefully ... >>> >>>> 4. You must make sure postfix is listening on the private IP address (at >>>> least). "netstat -lpnt | grep 25" will tell you what IPs postfix is >>>> listening on. >>> >>> >>> # netstat -lpnt | grep 25 >>> tcp 0 0 0.0.0.0:25 0.0.0.0:* >>> LISTEN 1494/master >>> >>> How do I read/understand that output? Shouldn't there be 192.168.10.1:25 >>> ? >>> (By the way: I didn't know postfix daemon is called "master" ,,,) >>> >>> >>> Greetings >>> >>> Peter >>> >>> >>>> ---------------------------------------------------------------------- >>>> - Rick Stevens, Systems Engineer, AllDigital ricks(a)alldigital.com - >>>> - AIM/Skype: therps2 ICQ: 22643734 Yahoo: origrps2 - >>>> - - >>>> - Errors have occurred. We won't tell you where or why. We have - >>>> - lazy programmers. - >>>> ---------------------------------------------------------------------- >>> >>> >>> -- >>> users mailing list >>> users(a)lists.fedoraproject.org >>> To unsubscribe or change subscription options: >>> https://admin.fedoraproject.org/mailman/listinfo/users >>> Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct >>> Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines >>> Have a question? Ask away: http://ask.fedoraproject.org >> >> >> >> > -- > users mailing list > users(a)lists.fedoraproject.org > To unsubscribe or change subscription options: > https://admin.fedoraproject.org/mailman/listinfo/users > Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct > Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines > Have a question? Ask away: http://ask.fedoraproject.org

Many ISPs block SMTP traffic TO their end users. Most also block outgoing SMTP traffic FROM their end users _unless_ it's going to the ISP's mail servers (this is to prevent end users from becoming spam farms). Assuming your ISP permits bi-directional SMTP traffic, here are things to look at:

Hi everyone, please do excuse my unspecific subject - I don't really know what my problem is yet. I set up a Postfix-Server on my Fedora 21 box, which is connected to the internet via some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora box fixed on 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for mydomain.com . Now I can - send myself mails from my Fedora box - send mails from my Fedora box to the outside p. ex. my googlemail account but I can't receive mails from outside. When I do a # tcpdump -n -i any tcp port 25 on my Fedora I can see many messsages like 10:34:09.338691 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019143 ecr 0,nop,wscale 9], length 0 10:34:10.339378 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019393 ecr 0,nop,wscale 9], length 0 [...] Any good ideas, what else I can do to analyze my problem? Thanks for your answers Peter .

> Now let's test something bad and completely turn of my firewalld !

-- users mailing list users(a)lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org

On 04/09/2015 02:34 PM, Peter Ulrich Kruppa wrote: > > > Am 09.04.2015 um 23:03 schrieb Mike Wright: >> >> >> On 04/09/2015 01:38 PM, Peter Ulrich Kruppa wrote: >>> Am 09.04.2015 um 22:06 schrieb Andy Blanchard: >>>> Yep. Get it on the same network as the server and run the command: >>>> >>>> telnet 192.168.10.1 25 >>> Now guess what - it says >>> >>> telnet: Unable to connect to remote host: No route to host >>> >> That's not good. >> >> Show us these: >> >> 1) ip a l (ip address list) >> >> 2) ip r l (ip route list) > From my laptop or from my server? From your mail server.

telnet: Unable to connect to remote host: No route to host Of course I can ping from my laptop to my server and vice versa ... Disabling SELinux didn't help.

On 04/09/2015 01:38 PM, Peter Ulrich Kruppa wrote: > Am 09.04.2015 um 22:06 schrieb Andy Blanchard: >> Yep. Get it on the same network as the server and run the command: >> >> telnet 192.168.10.1 25 > Now guess what - it says > > telnet: Unable to connect to remote host: No route to host > That's not good. Show us these: 1) ip a l (ip address list) 2) ip r l (ip route list)

On 04/09/2015 01:01 PM, Peter Ulrich Kruppa wrote: > > > Am 09.04.2015 um 21:53 schrieb Mike Wright: >> >> >> On 04/09/2015 12:46 PM, Peter Ulrich Kruppa wrote: >>> >>> Am 09.04.2015 um 21:30 schrieb Mike Wright: >>>> >>>> You can try running tcpdump to watch incoming connections while you >>>> send >>>> yourself an email from gmail/yahoo etc. That will let you know if >>>> mail >>>> is arriving and getting through your firewall. >>>> >>>> tcpdump -i eth0 port 25 (assuming single ethernet card). >>> This is, what I see, when an mail from outside arrives: >>> # tcpdump -i enp4s6 port 25 >>> tcpdump: verbose output suppressed, use -v or -vv for full protocol >>> decode >>> listening on enp4s6, link-type EN10MB (Ethernet), capture size 262144 >>> bytes >>> 21:39:21.951957 IP mail-wi0-f177.google.com.35438 > pukruppa.de.smtp: >>> Flags [S], seq 4222003974, win 42900, options [mss 1418,sackOK,TS val >>> 1017047302 ecr 0,nop,wscale 7], length 0 >> >> Yes. Between these two there should have been a reply from you, >> pukruppa.de.smtp > mail-wi0-f177.google.com.35438. >> >>> 21:39:22.951335 IP mail-wi0-f177.google.com.35438 > pukruppa.de.smtp: >>> Flags [S], seq 4222003974, win 42900, options [mss 1418,sackOK,TS val >>> 1017048302 ecr 0,nop,wscale 7], length 0 >>> >>> Does that say anything to you? >>> >> Which side of your router are you listening on, public or private? > Hmmmh, > > I am quite new to Fedora, but enp4s6 should be the NIC which connects my > server to my router. So it is the private side of my network, isn't it? That only tells me that it is the network card on your computer. I'm guessing that you haven't moved it and you are still connected to the inside of your router and have a non-routeable IP. If that is true your mail server does not appear to be answering requests.

> > >> If it's the public side that only shows that mail and dns are working >> from outside. Now you have to test from inside. >> >> If it's the private side it says mail is making through and your mail >> server is not answering.

Am 09.04.2015 um 20:52 schrieb Andy Blanchard: > > Hi Peter, > > 0.0.0.0 is a "wildcard"; Postfix is definitely running and listening > for incoming connections on port 25 on any IP address on your server. > > Do you have access to another PC or something on your internal network > that you can try connecting from? At least that way you could > determine whether you need to focus on the router or the server - > although based on your updates on FirewallD and Postfix, I'm leaning > more towards either the router or your ISP blocking SMTP by default at > present. Hi Andy, I have some old laptop running debian. Can I do something with it - without setting up another mail server on it? :-) > > On the latter point, it might be worth looking at their FAQ or maybe > contacting support just in case; some ISPs block SMTP by default as an > anti-spam measure but will open it up on request, but others require > you have some form of "premium" connection to host your own servers. > > Andy > > On 9 April 2015 at 19:16, Peter Ulrich Kruppa <pukruppa(a)googlemail.com&gt; > wrote: >> >> Am 09.04.2015 um 19:05 schrieb Rick Stevens: >>> >>> >>> On 04/09/2015 07:22 AM, Peter Ulrich Kruppa wrote: >>>> >>>> >>>> Am 09.04.2015 um 15:32 schrieb Robert Nichols: >>>>> >>>>> >>>>> On 04/09/2015 05:07 AM, Peter Ulrich Kruppa wrote: >>>>>> >>>>>> >>>>>> >>>>>> I set up a Postfix-Server on my Fedora 21 box, which is connected to >>>>>> the internet via >>>>>> some Netgear Router. My private LAN is 192.168.10.0/24 with the >>>>>> Fedora >>>>>> box fixed on >>>>>> 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, >>>>>> let's >>>>>> say for >>>>>> mydomain.com . >>>>>> >>>>>> Now I can >>>>>> - send myself mails from my Fedora box >>>>>> - send mails from my Fedora box to the outside p. ex. my >>>>>> googlemail >>>>>> account >>>>>> >>>>>> but I can't receive mails from outside. >>>>> >>>>> >>>>> >>>>> The default postfix configuration has it listening only on the >>>>> localhost >>>>> interface. You will have to change that. Look for "inet_interfaces >>>>> =" >>>>> in /etc/postfix/main.cf . >>>> >>>> >>>> I have got >>>> inet_interfaces = all >>>> in there. >>> >>> >>> >>> Many ISPs block SMTP traffic TO their end users. Most also block >>> outgoing SMTP traffic FROM their end users _unless_ it's going to the >>> ISP's mail servers (this is to prevent end users from becoming spam >>> farms). Assuming your ISP permits bi-directional SMTP traffic, here >>> are things to look at: >> >> >> It does - I had that working using a DSL bridge (modem) instead of a >> router. >> >>> 1. The outside world must send mail to the PUBLIC IP of your firewall >>> (not the 192.168.x.y address, but the one that's on the public >>> Internet). Make sure your MX DNS records reflect that public IP address. >>> If your MX records contain "192.168.x.y" or "10.x.y.z", then your record >>> is wrong (192.168.0.0/16 and 10.0.0.0/8 are non-routable, private >>> networks). >>> >>> 2. You must configure your external firewall to forward incoming port >>> 25 traffic to port 25 on your postfix machine's PRIVATE IP address. >>> >>> 3. Make sure firewalld on your postfix machine permits incoming port 25 >>> traffic. >> >> >> Points 1. to 3. should be allright - hopefully ... >> >>> 4. You must make sure postfix is listening on the private IP address (at >>> least). "netstat -lpnt | grep 25" will tell you what IPs postfix is >>> listening on. >> >> >> # netstat -lpnt | grep 25 >> tcp 0 0 0.0.0.0:25 0.0.0.0:* >> LISTEN 1494/master >> >> How do I read/understand that output? Shouldn't there be 192.168.10.1:25 >> ? >> (By the way: I didn't know postfix daemon is called "master" ,,,) >> >> >> Greetings >> >> Peter >> >> >>> ---------------------------------------------------------------------- >>> - Rick Stevens, Systems Engineer, AllDigital ricks(a)alldigital.com - >>> - AIM/Skype: therps2 ICQ: 22643734 Yahoo: origrps2 - >>> - - >>> - Errors have occurred. We won't tell you where or why. We have - >>> - lazy programmers. - >>> ---------------------------------------------------------------------- >> >> >> -- >> users mailing list >> users(a)lists.fedoraproject.org >> To unsubscribe or change subscription options: >> https://admin.fedoraproject.org/mailman/listinfo/users >> Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct >> Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines >> Have a question? Ask away: http://ask.fedoraproject.org > > > > -- users mailing list users(a)lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org

On 04/09/2015 12:46 PM, Peter Ulrich Kruppa wrote: > > Am 09.04.2015 um 21:30 schrieb Mike Wright: >> >> You can try running tcpdump to watch incoming connections while you send >> yourself an email from gmail/yahoo etc. That will let you know if mail >> is arriving and getting through your firewall. >> >> tcpdump -i eth0 port 25 (assuming single ethernet card). > This is, what I see, when an mail from outside arrives: > # tcpdump -i enp4s6 port 25 > tcpdump: verbose output suppressed, use -v or -vv for full protocol > decode > listening on enp4s6, link-type EN10MB (Ethernet), capture size 262144 > bytes > 21:39:21.951957 IP mail-wi0-f177.google.com.35438 > pukruppa.de.smtp: > Flags [S], seq 4222003974, win 42900, options [mss 1418,sackOK,TS val > 1017047302 ecr 0,nop,wscale 7], length 0 Yes. Between these two there should have been a reply from you, pukruppa.de.smtp > mail-wi0-f177.google.com.35438. > 21:39:22.951335 IP mail-wi0-f177.google.com.35438 > pukruppa.de.smtp: > Flags [S], seq 4222003974, win 42900, options [mss 1418,sackOK,TS val > 1017048302 ecr 0,nop,wscale 7], length 0 > > Does that say anything to you? > Which side of your router are you listening on, public or private?

If it's the public side that only shows that mail and dns are working from outside. Now you have to test from inside. If it's the private side it says mail is making through and your mail server is not answering.

On 04/09/2015 11:36 AM, Peter Ulrich Kruppa wrote: > Am 09.04.2015 um 18:18 schrieb Heinz Diehl: >> On 09.04.2015, Peter Ulrich Kruppa wrote: >> >>> To me this looks as if port forwarding is all-right but Postfix does >>> not >>> react (?!?) >> >> Take a look into the postfix log. > I can see postfix/master has been started and I can see activities when I > write myself an email from my server. But no messages about activities > from > outside. You can try running tcpdump to watch incoming connections while you send yourself an email from gmail/yahoo etc. That will let you know if mail is arriving and getting through your firewall. tcpdump -i eth0 port 25 (assuming single ethernet card).

Are you also hosting your own DNS? If not you can also try the same thing by booting from a thumb drive and listening on your public facing IP. Success will indicate both that your external DNS provider is pointing to you and that traffic is getting to your IP. Mike Wright

On 09.04.2015, Peter Ulrich Kruppa wrote: > To me this looks as if port forwarding is all-right but Postfix does not > react (?!?) Take a look into the postfix log.

To me this looks as if port forwarding is all-right but Postfix does not react (?!?)

I set up a Postfix-Server on my Fedora 21 box, which is connected to the internet via some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora box fixed on 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for mydomain.com . Now I can - send myself mails from my Fedora box - send mails from my Fedora box to the outside p. ex. my googlemail account but I can't receive mails from outside.

Hi everyone, please do excuse my unspecific subject - I don't really know what my problem is yet. I set up a Postfix-Server on my Fedora 21 box, which is connected to the internet via some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora box fixed on 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for mydomain.com . Now I can - send myself mails from my Fedora box - send mails from my Fedora box to the outside p. ex. my googlemail account but I can't receive mails from outside. When I do a # tcpdump -n -i any tcp port 25 on my Fedora I can see many messsages like 10:34:09.338691 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019143 ecr 0,nop,wscale 9], length 0 10:34:10.339378 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019393 ecr 0,nop,wscale 9], length 0 [...] Any good ideas, what else I can do to analyze my problem? Thanks for your answers Peter -- users mailing list users(a)lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org

On Thu, 9 Apr 2015 12:47:15 +0200 Peter Ulrich Kruppa wrote: [ ... ] > Yes: when I use telnet on port 25 from my Fedora I get > # telnet localhost 25 > Trying ::1... > telnet: connect to address ::1: Connection refused > Trying 127.0.0.1... > Connected to localhost. > Escape character is '^]'. > 220 pukruppa.de ESMTP Ok, let's test. # host -t mx pukruppa.de pukruppa.de mail is handled by 10 mail.pukruppa.de. # telnet mail.pukruppa.de 25 Trying 217.92.171.227... telnet: connect to address 217.92.171.227: Connection timed out There is no SMTP daemon listening for the outside world. I guess the missing port forwarding ist the problem.

--Frank .

Hi everyone, please do excuse my unspecific subject - I don't really know what my problem is yet. I set up a Postfix-Server on my Fedora 21 box, which is connected to the internet via some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora box fixed on 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for mydomain.com . Now I can - send myself mails from my Fedora box - send mails from my Fedora box to the outside p. ex. my googlemail account but I can't receive mails from outside. When I do a # tcpdump -n -i any tcp port 25 on my Fedora I can see many messsages like 10:34:09.338691 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019143 ecr 0,nop,wscale 9], length 0 10:34:10.339378 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019393 ecr 0,nop,wscale 9], length 0 [...] Any good ideas, what else I can do to analyze my problem? Thanks for your answers Peter -- users mailing list users(a)lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org

Hi everyone, please do excuse my unspecific subject - I don't really know what my problem is yet. I set up a Postfix-Server on my Fedora 21 box, which is connected to the internet via some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora box fixed on 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for mydomain.com .

Now I can - send myself mails from my Fedora box - send mails from my Fedora box to the outside p. ex. my googlemail account but I can't receive mails from outside.

On Thu, 9 Apr 2015 12:07:53 +0200 Peter Ulrich Kruppa wrote: > Hi everyone, > > please do excuse my unspecific subject - I don't really know what my > problem is yet. > > I set up a Postfix-Server on my Fedora 21 box, which is connected to > the internet via > some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora > box fixed on > 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for > mydomain.com . 192.168.10.1? Isnt .1 the adress of the router for 192.168.10.x? Maybe you should use a different IP. > Now I can > - send myself mails from my Fedora box > - send mails from my Fedora box to the outside p. ex. my googlemail account > > but I can't receive mails from outside. Is the postfix listening on port 25 (smtp)? If yes you need port forwarding on the router to send incoming connections on port 25 to the postfix host. Regards, Frank

Hi everyone, please do excuse my unspecific subject - I don't really know what my problem is yet. I set up a Postfix-Server on my Fedora 21 box, which is connected to the internet via some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora box fixed on 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for mydomain.com .

Now I can - send myself mails from my Fedora box - send mails from my Fedora box to the outside p. ex. my googlemail account but I can't receive mails from outside.

SMTP from external IP addresses (e.g. anything other than 127.0.0.1) is blocked by default by the Fedora firewall and I've not seen any mention of checking that in the thread. I'm assuming you are using the default firewall, FirewallD, rather than iptables?

If so: "sudo firewall-cmd --get-services" will list supported services. SMTP should be on the list. "sudo firewall-cmd --zone=public --list-services" will list permitted services in the public zone. SMTP should also be on the list. "sudo firewall-cmd --zone=public --add-service=smtp" will temporarily add SMTP to the permitted services if not present above. "sudo firewall-cmd --permanent --zone=public --add-service=smtp" will make that change permanent (survive a reboot). If you are using iptables, then you can check the rules with: "sudo iptables --list-rules" You should have an entry that reads something like: "-A INPUT -p tcp -m tcp --dport 25 --tcp-flags SYN,RST,ACK SYN -j ACCEPT" If not, you can add it by editing the file "/etc/sysconfig/iptables", adding the line above to the INPUT chain, then reloading the rules with the command "sudo iptables-restore < /etc/sysconfig/iptables". HTH On 9 April 2015 at 11:07, Peter Ulrich Kruppa <pukruppa(a)googlemail.com&gt; wrote: > Hi everyone, > > please do excuse my unspecific subject - I don't really know what my > problem is yet. > > I set up a Postfix-Server on my Fedora 21 box, which is connected to > the internet via > some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora > box fixed on > 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's say for > mydomain.com . > > Now I can > - send myself mails from my Fedora box > - send mails from my Fedora box to the outside p. ex. my googlemail account > > but I can't receive mails from outside. > > When I do a > # tcpdump -n -i any tcp port 25 > on my Fedora I can see many messsages like > > 10:34:09.338691 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], > seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019143 > ecr 0,nop,wscale 9], length 0 > 10:34:10.339378 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], > seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019393 > ecr 0,nop,wscale 9], length 0 > [...] > > Any good ideas, what else I can do to analyze my problem? > > Thanks for your answers > > Peter > -- > users mailing list > users(a)lists.fedoraproject.org > To unsubscribe or change subscription options: > https://admin.fedoraproject.org/mailman/listinfo/users > Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct > Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines > Have a question? Ask away: http://ask.fedoraproject.org

Hello! Am 09.04.2015 um 13:20 schrieb Bala Vishwanathan Iyer: > > Dear Mr. Kruppa > > I have some futher querries :- > > 1. Is this server your mail server for your domain. meaning does the > mail exchange record for your domain point to this server or some > other server. > > In case it it pointing to some other server say Google mail server or > any other hosting provider. Then I would suggest you install something > like fetch mail to get mails fro your mail server to your postfix > server. I believe that is what Frank Elsner was so nice to test from "outside" # host -t mx pukruppa.de pukruppa.de mail is handled by 10 mail.pukruppa.de. # telnet mail.pukruppa.de 25 Trying 217.92.171.227... telnet: connect to address 217.92.171.227: Connection timed out > 2. can you telnet your postfix servers external ip on port 25 from > outside your network. > > If no, then that is the issue. Yes, but what can I do? port 25 seems to point to my Fedora box. Regards Peter Kruppa > > Regards > Bala V Iyer > > On Thu, Apr 9, 2015 at 3:37 PM, Peter Ulrich Kruppa > <pukruppa(a)googlemail.com&gt; wrote: >> >> Hi everyone, >> >> please do excuse my unspecific subject - I don't really know what my >> problem is yet. >> >> I set up a Postfix-Server on my Fedora 21 box, which is connected to >> the internet via >> some Netgear Router. My private LAN is 192.168.10.0/24 with the Fedora >> box fixed on >> 192.168.10.1 . My Netgear thing has got a fixed IP and hostname, let's >> say for >> mydomain.com . >> >> Now I can >> - send myself mails from my Fedora box >> - send mails from my Fedora box to the outside p. ex. my googlemail >> account >> >> but I can't receive mails from outside. >> >> When I do a >> # tcpdump -n -i any tcp port 25 >> on my Fedora I can see many messsages like >> >> 10:34:09.338691 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], >> seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019143 >> ecr 0,nop,wscale 9], length 0 >> 10:34:10.339378 IP 212.227.17.11.64945 > 192.168.10.1.smtp: Flags [S], >> seq 3273717964, win 14600, options [mss 1418,sackOK,TS val 1273019393 >> ecr 0,nop,wscale 9], length 0 >> [...] >> >> Any good ideas, what else I can do to analyze my problem? >> >> Thanks for your answers >> >> Peter >> -- >> users mailing list >> users(a)lists.fedoraproject.org >> To unsubscribe or change subscription options: >> https://admin.fedoraproject.org/mailman/listinfo/users >> Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct >> Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines >> Have a question? Ask away: http://ask.fedoraproject.org -- users mailing list users(a)lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org