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How can you tell if emails are coming in to server? 2

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We are not getting any incoming emails, we can send out going ones, but do not get incoming.

we have switched isp's, so the MX records are supposed to have been changed, yet they still do not come in.

I thought I had configured the router and the firewall right, but still nothing. how do I find the blockage?
 
If you just switched ISP and thus MX records, it will take a few hours.
If still problems after 24 hours, contact your ISP first!

Marc
If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
Free Tip: The F1 Key does NOT destroy your PC!
 
Have you actually checked the MX records to see if the change has been made?

Chris.


**********************
Chris Andrew, CCNA, CCSA
chris@iproute.co.uk
**********************
 
Of course, but that is no immediate garantee, if you check them from your ISP, they may show, but that does not mean they are already 'worldwide', hence the waiting a few hours.
 
Yes, but he's not sure that the ISP has in fact made the change. He said " so the MX records are supposed to have been changed".

I was simply suggesting that he check that the work has been done by the ISP so that he can be sure that it will work when the zone has propagated.

For future reference, when changing DNS providor or simply changing any records it is a good idea to have the TTL's lowered a few days before the changeover. I always have the TTL lowered to 900 seconds so that the change will propagate world wide in a very short time.

Chris.


**********************
Chris Andrew, CCNA, CCSA
chris@iproute.co.uk
**********************
 
Very true.
I was also just meaning that, even if the MX records appear to be ok, it could take some time to get around.
But, by the time these posts are done, it may well be ok already.
 
GreenTeeth, if you post your domain name, we can check your DNS record, and see what MX record is listed.
 
Good idea, but .. bad idea to post that here.
Everyone can read that, even non-members, and there is always 'the bad guys' looking for such info (SPAM etc).
He best calls a friend or a contact on MSN or so, somewhere far away to check that for him.
 
Well, I agree that its good to be cautious, but domain names are in the public domain. And dns records are publicly available as well, otherwise you wouldn't be able to send email to anyone.

The bottom line is, that its not really a security risk to post your domain name. Can you demonstrate otherwise?
 
It is indeed public domain, obviously for the reasons you mention.
But I invite you to find out mine if I don't give it here.

My point is, someone can always look up any name, but if it is clearly anounced here or anywhere else, the get the domain name, know there is a mailserver and other info that may get posted here.
That is the added risk. It like feeding those bad boys the info with a spoon.
 
The 'bad guys' don't go searching forums for mail server domain names they run automated scans for open port 25 on a range of IPs then they can call a telnet session to get the domain name from that if they want.
Spammers run spiders to 'harvest' the mailto:someone@somewhere.com anchors from webpages, guestbooks, message boards and forums.
placing a domain name on an open forum like this can actually help with getting the domain better rankings on the search engines.
if you are that paranoid post the IP in octets without the dots then a reverse DNS lookup can be used manually

Chris.

BTW. If you want to see how well the message board domain name spamming works for SEs, google "replica watches" with or without quotes, see how many unrelated message boards are in the top ten!



Indifference will be the downfall of mankind, but who cares?
 
Sorry Chris, but I find it a little simplistic to say that anyone would be paranoid if they avoid public posting a domain name.
There are enough horror stories around, mostly from the less paranoia. And believe me, I know how these guys do it, I happen to work at an internet security company.
There is dozens of ways to do it, all I am saying, again, is not literaly give it away.
As an argument to your statement about the scanning, I can say you could scan our systems and will not find anything with a ping or portscan. Not even a Telnet will get you anywhere, the firewall will just not answer if the request does not come from where I told it it should accept it from. So there is ways to shield yourself from them, it just takes an effort and a consistent management of your protections.
Every system is only as good as the weakest point, and that is, sadly, most of the time .. the mailserver.

But we are getting into a whole different area here and that is not going to help Greenteeth.
 
Greenteeth,

You have my email address so if your mail continues to be a problem then email the domain and I'll have a look. If you are now getting mail then all is well.

Chris.


**********************
Chris Andrew, CCNA, CCSA
chris@iproute.co.uk
**********************
 
Most amusing.

I haven't had so much fun since crackerjack was on (erm, that's not strictly true, before you start getting ideas)

Actually, I checked whith the ISP, and it turns out that they haven't done it yet. Which is a pain in the bum, as this particular ISP only do a refresh once a day, soo it will now be tomorrow, even if they pull their finger out today.

I take it that there is nothing that I can check over the net to see if it has been done, is that because I don't know what I am doing, or because it is a data protection thing.

I am basically trying not to go down roads that don't go anywhere. I've done that for the past 2 days. It feels like tring to chop lettuce with a rolling pin, it will take you hours and won't be very effective.

Thanks for your help, I shall plunge onwards.
 
Open a MD prompt
type: nslookup
then type: set type=mx
then type: your domain name.

If the mx record returns your new IP address, your set to go.
 
hi, when I type this in, I just get bad command or file name.

How should I be typing this?

Still no emails by the way.
 
On your Exchange server, open a command prompt, and then:

nslookup
set type=MX
abc.com

Where abc.com is your domain name.
 
I guess I needed to add "hit Enter now" on every line ;-)
 
Ah ha, no it was the bit about do it on the exchange server that i needed.

Now i have lots of numbers and i don't know what they mean....lol

Oh, ok, a few lines down, I can see what I guess is my email server and then internet address.

Would it look something like this for example:
emailservername.domainname.com Internet address = 1.2.3.4

?

and would this mean that our isphas changed the mx records correctly.

If so, they still aren't filtering in yet, is it possible it takes 24 to filter everything through their system?
and so hopefully we shall have them tomorrow?
 
You can do that on any PC on the LAN, it should not matter where you do that from.

the one you want is where is says MX, that should be your IP.
If not, contact the ISP

Marc
If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
Free Tip: The F1 Key does NOT destroy your PC!
 
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