i want to create mx record in aws r53 like this. my domain is in godadday
1) Host as # and points to as smtp.secureserver.net with priority 0 and TTL one hour.
2) Host as # and points to as mailstore1.secureserver.net with priority 10 and TTL one hour.
bust while creating this error flash .The record set could not be saved because:
- The Value field contains invalid characters or is in an invalid format.
If your image is accurate, the priority needs to proceed the FQDN
Your example shows:
smtp.secureserver.net
And should be:
0 smtp.secureserver.net
The following worked for me
Related
I have a hosted zone created in Route53 and updated the NS records under the namespaces of the purchased domain.
Unfortunately the DNS check does not return or point to the new NS records instead gets resolved to old/ previously existing records.
I waited more than 72 hours and still i get "This site can’t be reached"failing with error DNS_PROBE_FINISHED_NXDOMAIN in the browser.
Below is a screenshot from the DNS check provided by https://mxtoolbox.com/,
It shows that the old NS records (First 4 rows with TTL to 48 hours) are present in the Parent and not in local whereas the newly updated records (The last 4 records) are present in the parent and not in the local.
Ping to the domain fails with Unknown host.
What are the next steps?
When you update the name servers for a domain, remove the old name server records.
Your TTL is set to 48 hours. That means any recursive resolver such as dns.google will not refresh for 48 hours after last update. For resolvers that have not cached your resource records, they might update immediately but might also get stale data from an upstream resolver. Wait a few hours so that you do not force a new cache load with old data and then check with an Internet tool such as dnschecker.org Change the selection box from A to NS to see the name server changes.
In general I recommend that it takes 48 to 72 hours for authoritative name server changes to propagate around the world.
Google DNS supports "Flush Cache". Wait an hour or two and then request that Google update their DNS cache. Flush Cache
Cloudflare also supports Purge Cache
Google and Cloudflare are very popular DNS resolvers.
Also, do not forget to flush your local computer's DNS cache:
Windows: ipconfig /flushdns
Linux: sudo service network-manager restart (ubuntu) or sudo /etc/init.d/nscd restart
macOS: sudo dscacheutil -flushcache followed by sudo killall -HUP mDNSResponder
I have the following traffic policy document in AWS
Weighted Resource Record Set Weighted Resource Record Set
---------------------------- ----------------------------
Name: www.example.com Name: www.example.com
Type: A Type: A
Value: 192.0.2.11 Value: 192.0.2.12
Weight: 1 Weight: 3
And based on the above document 25% of the requests should hit 192.0.2.11 and 75% of the requests should hit 192.0.2.12.
e.g. If I send 4 concurrent requests to www.example.com 3 should hit 192.0.2.12 and 1 should hit 192.0.2.11, but this is not happening.
What I observed is that first few requests will hit only 192.0.2.11 and after some time it hits only 192.0.2.12.
Is this the default beahaviour?
Weighted RRs don't exhibit the behavior you are expecting on a small scale like this. It is a statistical behavior, not an active load balancing mechanism.
If you were to have 1000 people make 1000 requests at 1000 randomly selected times, you would expect to see approximately 250 requests go to one endpoint and 750 requests go to the other.
By the nature of DNS and browser DNS caching behavior preclude you from seeing such a split on small numbers of requests, particularly concurrent requests from a single client. The more typical outcome is that you will see a 25%/75% split of which server each viewer will connect to and often tend to stick to for some period of time.
If you repeat your test 1000 times, you should again see numbers closer to the expecte split. Longer TTLs on your DNS records will also tend to cause your test results to be less consistent with the weights, if the times between your tests are short. Shorter DNS TTLs will not be ideal for overall performance, but you might try temporarily setting the TTL to 0 and test again to see what results you get.
Remember, though, that a TTL change doesn't take effect until the time since the TTL change exceeds the old TTL value. If, for example, the old TTL was 300 seconds, you are not assured of the new TTL having an effect until at least 300 seconds have passed since the time you changed the TTL (plus about 30 seconds for internal Route 53 propagation of the change).
I am trying to learn how writes/updates work internally in DynamoDB. This is what I could find.
AWS Tutorial Link
"When your application writes data to a DynamoDB table and receives an HTTP 200 response (OK), all copies of the data are updated. The data will eventually be consistent across all storage locations, usually within one second or less."
For ex: If my DynamoDB has 50 partitions and it is replicated across 3 availability zones in a region, what happens in DynamoDB
After it receives an API request to create an item
After it sends the 200 OK response to the client
I would really appreciate any document that talks about this or hear from you directly.
Thanks
Dynamodb as per this replicates its data in 3 availability zones within the region.
So the question is how it manages the availability of the data.
Assume there is one receiver which will receive the request from the users.
The receiver for write request will have m/n value for consistency of data.
n is the number of availability zones
m would be ((n+1)/2) to maintain consistency.
In this case, it is 2/3.
Now when a receiver receives any request it will send the command to write data to all 3 zones but will wait for 2 zones to respond. When 2 of the zones has written the value the receiver will send 200 OK to user without waiting for zone 3 to respond.
Let say that user now immediately want to retrieve the data which was written.
For read request the receiver will use 1/(number of availability zones), In this case it is 1/3.
So receiver will request all the zone for data, Let say that zone A respond, This respond will be immediately sent to user.
Assuming 2/3 write request the data is stored in Zone A and Zone B currently, Zone C is still not updated.
Now when we read data if Zone A or B respond then we will have the value if Zone C respond then it will result in not found, this is the reason AWS say dynamoDB is eventual consistent.
When we query data with strongly consistent read, the value change to 2/3 which will make sure that updated value will be sent to user because at a time 2 availability zone will have the newest value
Note: This is just a simplified explanation and I am not associated with Amazon, they might be using some other things behind the scene.
Hope that helps
I am trying to setup an email server using an EC2 instance(postfix)
I am trying to understand the value "10 mailserver.domainame.com".
does it mean I must do "hostname mailserver.domainame.com" on my email server? which means having mailserver.domainame.com as the hostname?
what about the number "10"?
thanks.
10 is the "cost" of the mail exchanger. If you had a primary and a backup, you'd set the backup as a higher value, such as 20... so that servers trying to deliver mail to your domain would try the "lowest cost" (10) before the higher cost (20) server, and only use the 20 machine if they found the 10 machine inaccessible. The number 10 is arbitrary. It could be 5 or 0 or 17. It has no real meaning if you only have one mail exchanger, but is still required.
You do not need to set the internal hostname of the machine at mailserver.example.com. Nobody really sees or cares about that except you. As long as you have a DNS A record for mailserver.example.com that returns the correct IP address, that is sufficient for MX configuration.
I wants to use Fast mail service for receiving all mails of my website but stuck in configuring the MX Record from Route 53.
I have added the MX record like this:
Name: mail.locate.ie.
Type: MX
Values:
10 in1-smtp.messagingengine.com
20 in2-smtp.messagingengine.com
When I'm testing for MX record I have found error saying:
The domain you have tested (locate.ie) does not have MX records that point to our servers. The MX records we detected are: (none)
And also no MX record were showing from other online DNS Tools like MXlookup.
Please anybody tell me what I have not done correct to point the MX to FastMail Servers.
It looks like you created the MX record under mail.locate.ie. What this mean is that only mail destined for mail.locate.ie will work. What you will need to do is create an MX record with the name field empty and put the same values in.