IP addresses Virtual Networks Module 1.2.2 Flashcards
How are internal IP addresses assigned to VMs
When you create a VM in Google Cloud, its symbolic name is registered with an internal DNS service that translates the name to an internal IP address.
The DNS is scoped to the network, so it can translate web URLs and VM names ofhosts in the same network, but it can’t translate host names from VMs in a different network.
which gsp services depend on VMs and there fore have internal IPs assigned
App Engine and Google Kubernetes Engine
What are types of external IP addresses
external IP address, is optional.
You can assign an external IP address if your device or machine is externally facing.
That external IP address can be assigned from a pool, making it ephemeral, or it can be assigned from a reserved external IP address, making it static.
Which resources use static IP addresses and what to be aware regarding charging.
VM instances and forwarding rules can use static IP addresses.
If you reserve static external IP address and do not assign it to a resource, such as a VM instance or
a forwarding rule, you are charged at a higher rate than for static and ephemeral external IP addresses that are in use.
Can you use your own IP address in GSP
You can use your own publicly routable IP address prefixes as Google Cloud external IP addresses and advertise them on
In order to be eligible, you must own and bring a /24 block or larger.
Are there limits on how many instances can be per network
You might have a very large IP range but that doesn’t mean that you actually can create that many instances. That’s a quota.
There may also be actual limitations on physical hardware that’s even available within a specific region or zone. (it was 15,000) Example with the slash 20 we have over 4,000 addresses.
Does internal IP address change when VM is restarted
No internal IP address stays the same but external if it is ephemeral changes. But if you delete and recreate VM internal IP can change.
Does OS of the VM knows of its external IP address
It doesn’t, regardless of whether you use an ephemeral or static IP address, the external address is unknown to the OS of the VM.
The external IP address is mapped to the VM’s internal address transparently by VPC.
Instead, the network stores a lookup table that matches external IP addresses with the internal IP addresses of the relevant instances.
How does DNS resolution work for internal IP adresses
Each instance has a host name that can be resolved to an internal IP address.
This hostname is the same as the instance name.
There’s also an internal fully qualified domain name, or FQDN, for an instance that uses the format [hostname].[zone].c.[project-id].internal.
DNS name always points to a specific instance, no matter what the internal IP address is. (so if the IP internal address change, connection stays stable)
what is googles service for hosting DNS (Domain name servers )
Domain name servers can be hosted on GCP, using Cloud DNS.
Cloud DNS is a scalable, reliable, and managed authoritive Domain Name System, or DNS, service running on the same infrastructure as Google.
GCP offers a 100% uptime Service Level Agreement, or SLA, for domains configured in Cloud DNS.
Each instance has a metadata server what id does
metadata server acts as a DNS resolver for that instance.
The metadata server handles all DNS queries for local network resources and routes all other queries to Google’s public DNS servers for public name resolution.
What are Alias IP ranges
Alias IP Ranges let you assign a range of internal IP addresses as an alias to a virtual machine’s network interface.
This is useful if you have multiple services running on a VM, and you want to assign a different IP address to each service.
What is CIDR
Classless Inter-Domain Routing (CIDR) is an IP address allocation method that improves data routing efficiency on the internet.
