I am trying to configure aerospike to work in AWS. The recommended settings are to use Hearbeat mode mesh. Now I'm trying to use DNS say trial.example.com instead of IP in
mesh-seed-address-port 192.168.1.100 3002 in this config but am unable to do so. The problem is the cluster visibility is shown False in AMC. Can someone please help?
(I work at Aerospike). Specifying a DNS entry instead of an IP address in the mesh-seed-address-port is currently not supported. So you will have to use an IP address (or a list of IP addresses). This is something that we may support at some point in the future.
Related
I am very much new to network programming and maybe I am asking a very basic question.
I am working on a legacy C++ codebase where the windows 'getnameinfo' API is used to obtain the hostname from the given IP address. The obtained hostname is wrong and it belongs to a different VM in the domain.
Let us say, there is VM with hostname 'VM1' with IP 10.44.176.57 and
another VM with hostname 'VM2' and IP 10.44.176.24.
When IP 10.44.176.57 is passed to the getnameinfo() API, it resolves it to the hostname VM2.
The ping command also returns the same results.
When I ping hostname VM1 and VM2 both resolves to their correct respective IP addresses.
I checked in DNS manager, the IPs of VMs are assigned correctly.
My question is,
1) Why getnameinfo API is returning the wrong hostname?
2) Is there any way to verify the resolved hostname is the correct one ?
I have a domain that I own. I will say is example.com. I added SSO.example.com as a Type A record on GoDaddy with a value of 37.89.245.2(example).
The IP address is a elastic IP on a Windows AWS server.
I can ping the IP address but I can't ping the URL. Do I need to do something with the IP address on the AWS Windows server to be able to ping the URL?
This is pretty much one of my first web based projects so any help would be appreciated!
Ping is not a reliable test method in AWS because most security groups do not permit inbound ICMP protocol, which is used by Ping. So, if you really want to test connectivity, do it on a port that you actually need your application to support, such as HTTP (80) or trying an SSH/RDP connection.
Another common use for a Ping is to resolve the domain name to an IP address, since it displays the result on-screen. This can be a good way to check that your Amazon Route 53 configuration is correct. (Same as a dnslookup.)
I was jumping the gun a bit and the new NameServers I was using had not replicated completely yet. After replication completed everything was able to be pinged successfully.
I want to add multiple routable ip addresses to an ubuntu 14.04 GCP instance. What is the simplest method for achieving this?
Note: External IP addresses are disabled on my gcp instances.
Correct me if I am wrong, but the solution described in this post that uses gcloud routes seems to change the network and firewall configuration to add extra IP addresses to instances. I am looking for a different solution.
I would like to add IP addresses to instances without changing the networks or firewalls of a gcp project at all.
I would like to add random available IP addresses on the current network of a gcp instance and avoid manually assigning an IP address or IP address range to my instances?
I am really looking for a solution that is similar to openstacks nova add-fixed-ip command that does just this. You can find a description of nova add-fixed-ip here: https://ask.openstack.org/en/question/65198/how-to-assign-static-private-ip-address-to-a-running-guest-vm/
There is a topic in EC2 documentation Changing the System Hostname. Why does one need to change it? Just for fun? Just to have some nice shell prompt?
// change this
ubuntu#ip-123-12-1-231 ~ $
// to this?
ubuntu#my-beautiful-hostname ~ $
I'm learning how AWS DNS work, where my EC2's DNS lives that resolves a default Public DNS name to Public IP address of my instance
Public DNS: ec2-xx-xx-xxx-xx.ap-southeast-2.compute.amazonaws.com
Public IP: xx-xx-xxx-xx
And how can I host multiple apps with real domain names (example1.com, example2.com, so on) in one EC2 instance, how to modify and manage DNS. And actually I don't know what to read about it in docs, and read everything related to hostnames and DNS, and found this topic Changing the System Hostname and don't understand why would one want to change a hostname and if it can be valuable info for me.
UPD:
And now a real a practical question for those specimens who like closing questions quietly.
Where does a DNS live in EC2 instance? How is Public DNS mapped to Public IP? Where is that record in my EC2 Ubuntu instance? Is Route53 involved in it?
Where does a DNS live in EC2 instance?
It doesn't, DNS resolution use by the server is set in /etc/resolv.conf and /etc/nsswitch.conf. The hostname domain name for that server is set (Redhat derived systems) in /etc/sysconfig/network
How is Public DNS mapped to Public IP?
With a DNS record
Where is that record in my EC2 Ubuntu instance?
In the DNS for the domain that you have attached it to
Is Route53 involved in it?
Only if you are using Route53 for DNS
EC2 DNS location (source):
In EC2-Classic, the Amazon DNS server is located at 172.16.0.23.
In EC2-VPC, the Amazon DNS server is located at the base of your VPC network range plus two.
For more information, see Amazon DNS Server in the Amazon VPC User Guide
Well i had the same issue as you did and someone replied me this
It isn't a huge deal if you are just running a single server, mostly
to help you identify a server with local networking. Some things like
mail servers will use your hostname unless you specify otherwise.
This is an example of somewhere I saw that done
My original query
why do some people set hostname and some dont? whats the use?
hostnamectl set-hostname
I have a web service running on aws under the following URL http://"54.194.164.164:8080"/webapi and the instance is associated with an Elastic IP 54.194.164.164. Now i want to add a DNS record so that i can access this easily like htttp://demo.mydomain.com/webapi.
what i have done so far is, i have added an A record called demo.mudomain.com to 54.194.164.164 in the Godaddy DNS console but still i cant access demo.mydomain.com/webapi.
Can you please guide me what i have to do where i can access the web service easily as demo.mydomain.com/webapi
Thanks
saththiyan
You can't do this. DNS maps names to IP addresses but not ports.
If you are going to access HTTP at an address it has to be:
Bound to the default port (80) if you don't want to specify the port.
Specified in the URL if it is a different port.
If you are trying to do this for an "easier" address you'll have to use port 80. If that is used by something else you are stuck with nominating a specific port.
You could consider assigning another ip address and setting up an address like api.mydomain.com to point to it. That way you could use http://api.mydomain.com/webapi by binding the API to that address rather than http://demo.mydomain.com which you are presumably using for something else.