Questions tagged [ipv4]
Refers to the 4th revision of the Internet Protocol, where addresses are usually displayed in the form of dotted decimals between 0-255. Ex: 169.254.0.1
460
questions
1
vote
1
answer
211
views
How to better understand IPv6 to block requests
With IPv4, whenever I realize any strange requests coming to my server I can easily block the IPv4 from further requests (I can block on my iptablets, or in my .htaccess file...). However with IPv6 it'...
0
votes
1
answer
448
views
Link-local IPv4 network scope on Windows
We have an embedded PC that initially starts off life with a link-local IPv4 address, typically 169.254.0.1. It broadcasts its existence using Zeroconf using the python-zeroconf library. These ...
2
votes
1
answer
298
views
All Outbound Traffic Uses IPV6
I have a Debian 10 server which has postfix installed, each time I try to send outbound mail traffic, the server uses IPV6 over IPV4. This causes postfix to log Connection timed out.
I have tried ...
1
vote
1
answer
811
views
Can I have two DHCP servers for IPv4/IPv6?
I have an IPv6 block, However the network is based on an IPv4 only router. I can't change that router for several reasons.
Can I have a DHCPv6 server with DHCPv4 server? Or do I have to disable DHCPv4 ...
2
votes
3
answers
455
views
How do I visit ipv4 addresses (not domain) from an ipv6-only network?
I got an ipv6-only server and I want to visit ipv4 addresses like 8.8.8.8 with it. I know that I can visit ipv4-only website through DNS64 and NAT64. However, if the destination is just an ipv4 ...
0
votes
1
answer
1k
views
SSRS 2019 not listening on IPv4 Ports, only iPv6
We installed SSRS 2019 on a Windows Server 2016 without any problems and configured it to use URLs with port 80.
Accessing those URLs (Service and Portal) via local browser works fine, but trying to ...
0
votes
1
answer
157
views
How does a node differentiate between an IPv4 and IPv6 datagram? [closed]
In a computer network, how do hosts and routers tell if a datagram is IPv4 or IPv6? Do they just look at the version number field of the packet header?
0
votes
0
answers
211
views
iptables -> ip6tables (convert)
I have the following iptables (ipv4) and need the same on ip6tables (ipv6) for an openVPN-Server:
# Flushing all rules
iptables -F FORWARD
iptables -F INPUT
iptables -F OUTPUT
iptables -X
# Setting ...
19
votes
3
answers
4k
views
What is the name of an IP prefix with prefix length 31? (i.e. contains only 2 IP addresses)
At my job, IP prefixes with prefix length 31 (i.e. they only fit 2 IP addresses) are commonly described at "linknet addresses". Lately I have noticed that this term doesn't appear to exist ...
-1
votes
1
answer
34
views
Is the network part of an IPv4 address unique? [closed]
I get that an IPv4 address can be subdivided into two parts, the network part and the host part.
In my private home network, is the network part publicly unique?, i.e., may other people have the same ...
2
votes
0
answers
650
views
Using 'netsh interface ip set address' to override another adapter's address?
I'm one of the developers of the OpenConnect VPN client.
We're trying to modernize and improve our support for Windows. We use a user-customizable JScript called vpnc-script-win.js to configure IPv4/...
0
votes
1
answer
814
views
Ubuntu Server 20.04: IP address in use
I have a bare metal dedicated server with a UK hosting company.
They have an automated system which keeps blocking my server because they claim that I am using an unauthorised IP address. The IP ...
3
votes
2
answers
5k
views
Fresh Ubuntu 20 server getting wrong DHCP address
I need to setup a new Linux server on VirtualBox, I'm using Ubuntu Server 20.04 LTS and in Virtualbox my network adapter is set to bridge adapter with promiscuous mode on "allow all"
First ...
4
votes
1
answer
2k
views
Configuring dnsmasq to filter A or AAAA queries
Can I configure dnsmasq to respond to either ipv4(A) or ipv6(AAAA) queries only?
I am using dnsmasq to forward queries from an internal subnet to a WAN connection.
Unfortunately, sometimes I will only ...
1
vote
1
answer
3k
views
Get-NetIPInterface property 'Dhcp' is 'Enabled' after setting static IP configuration with netsh
The Question
Set a static IP configuration with netsh:
netsh interface ipv4 set address name="Ethernet1" static 192.168.0.20 255.255.255.0 192.168.0.1
netsh interface ipv4 set dns name="...
1
vote
1
answer
533
views
Why can't my internal IP addresses be granted access from IIS 10 IP Address and Domain Restrictions?
Why can't my internal IP addresses be granted access from IIS 10 IP Address and Domain Restrictions?
Backstory:
I have implemented IIS 10's IP Address and Domain Restrictions to block access to one ...
1
vote
0
answers
215
views
Squid in dual stack ipv4 / ipv6 reaching out for services only served on ipv4 interface
I am running a dual stack network and am running a server there (Squid, Apache, DHCP, Mail,...). The network is working properly. However not all services running on that server provide a listener on ...
5
votes
1
answer
12k
views
Make Docker listen to the IPv6 address of server, forward IPv6 requests to right container
My server is running on both IPv4 and IPv6. Docker is running on (local) IPv4 addresses (ie 192.168.100.1/24). I did not enable IPv6 inside daemon.json as I understand that to be rather buggy and ...
1
vote
2
answers
2k
views
How to tag IPv4 and IPv6 packets with different VLAN tags on a Linux box?
I want to tag incoming IPv4 and IPv6 packets from a dual stack enabled connection with different VLAN tags, e.g. IPv4 packets should go to VLAN4 and IPv6 packets should go to VLAN6. To be more general,...
3
votes
1
answer
3k
views
ping returns IPV6 address on ubuntu 20.04
I have installed GitLab on a cloud VM and shortly after stood up a second VM as a postfix server with the same provider (Hetzner)
I first noticed a problem when I went back to the GitLab server to ...
0
votes
1
answer
997
views
AWS EC2 Instance Public DNS includes IP address
My AWS EC2 instance's public DNS has the public IP address in it separated by -. For example:
ec2-x-xx-xxx-xxx.ca-pacific-x.xxx.amazonaws.com.
Now, my question is when I give my users this DNS, is it ...
0
votes
1
answer
5k
views
Why does setting MTU 1452 solve Internet problems and how to fix root cause?
In our church we get Internet uplink from a friendly neighbor’s WiFi. At first everything seemed (at least) fine but since some weeks general “Internet stability problems” increased and since approx. ...
0
votes
1
answer
699
views
Is it possible to check that given IPv4 and IPv6 belong to the same NIC?
Given an IPv4 and an IPv6 address of a machine and only access to the public services it provides, is it possible to check that they are assigned to the same network interface controller? Assume the ...
0
votes
0
answers
119
views
Are there issues if you run a IPv6 private network with IPv4 values and an empty prefix?
So i recently found out that the last 32 bits of an IPv6 can be addressed by their decimal value (not universally, busybox ping doesn't).
So your IPv4 network is 10.0.0.0/8 and your IPv6 is ::10.0.0.0/...
0
votes
1
answer
227
views
Synthesize A records when only having AAAA [closed]
I'm hosting some things from my home network and my ISP doesn't provide me with an IPv4 address. Not with a way to port forward to it anyway.
I've got my servers running using IPv6 and everything ...
0
votes
1
answer
109
views
Azure: Difference between IPv4 and IPv6 single IPs versus bundle
I want to assign public IPs to my services (IPv4 and IPv6 are needed) but I can choose to either:
Assign a dedicated IPv4 Address
Assign a dedicated IPv6 Address
Assign a bundle - of an IPv4 and IPv6 ...
1
vote
1
answer
1k
views
Is it possible to create an Elastic IP address from the current IPv4 address of my ec2 instance?
I currently have an ec2 "t2.nano" instance up and running. I would like to switch to a "t2.micro". In order to do that, I need to stop the instance. But I would lose my IPv4 ...
1
vote
2
answers
4k
views
My public IP is IPv6, but I thought I had a static IPv4
I have a commercial, small business service from COMCAST which includes I think 4 or 5 static IP addresses. I have one computer that is wired directly into the COMCAST modem and statically configured ...
1
vote
1
answer
342
views
IPv4 Address Range Shortage Inquiry
Recently I was looking over RFC6890 (link here) to find out more about the current IP addressing schemes that are in place and noticed a rather large IP address range that is listed as "Reserved ...
1
vote
1
answer
8k
views
Can i use a proxy from ipv6 to ipv4
Suppose i have an ipv6 internet address. Is it possible to connect to a ipv4 proxyserver. I have been trying this scenario from ipv4 which works perfectly, but not with ipv6. Could this be the cause?
-3
votes
1
answer
304
views
Is there a global shortage of IP addresses or not? [closed]
This is bugging me a bit, so would like some help. Here's some data I've gathered:
Apparently, an IPv4 address can range from 0.0.0.0 through to 255.255.255.255, providing up to 4,294,967,296 unique ...
-1
votes
1
answer
268
views
Banning an IP address
I banned an IP on my server, but I'd also like to ban using the CIDR method, e.g. IP/24.
My questions are:
How do I find the CIDR range of the IP address.
When banning the range, if the user has a ...
1
vote
1
answer
349
views
Confused about routing and netmasks
I'm having some issues with OpenVPN and multiple VPNs. Not earth shattering, but after bringing up a combination of VPNs I didn't intend to I've ended up in a situation I don't understand. Looking at ...
7
votes
2
answers
8k
views
Why 224.0.0.1 traffic is filtered by Linux hosts?
When sending an ICMPv4 echo request to a destination address like 224.0.0.1, it is ignored by Linux hosts receiving the request. The destination MAC address used is 01:00:5e:00:00:01.
The only way to ...
0
votes
2
answers
537
views
confused about CIDR interpretation
I am beginner in networking and trying to understand subnetting. What I understood is that
CIDR notation (Classless Inter-Domain Routing) is an alternate method of representing a subnet mask. It is ...
0
votes
1
answer
300
views
Cannot display default NGINX page
I just installed Ubuntu 20.04 on my server. I also installed Nginx.
My problem is that the default sie Nginx page is not displayed. Yet UFW is not activated.
Do you have an idea of the problem ?
This ...
0
votes
0
answers
93
views
Removing IP address from server takes down unrelated website
I'm working with a Windows 2008 Server running IIS. One of the websites running in IIS was migrated to another server. As a result, I shut down that site in IIS on the Windows 2008 server. There weren'...
1
vote
1
answer
1k
views
Can't ping host with two interfaces
I am trying to figure out why a network interface is not pingable and is returning an ICMP type 3 code 1 response: Destination unreachable (host unreachable).
I am trying to ping from host1 to one of ...
0
votes
1
answer
155
views
Why would hostname -I report 3 IP addresses?
Environment: Fresh install of CentOS 8, Digital Ocean Droplet
Question: Why would hostname -I report 3 IP addresses? Shouldn't it show 1 IPv4 and 1 IPv6 address?
My Output: (IP addresses changed)
...
2
votes
1
answer
938
views
What may cause a request being sent with a TTL of 64 to fail on connection to a destination ip that traceroute shows is 33 hops away?
From within a docker container (running ubuntu 18) running on AWS ECS I'm attempting to establish a connection to an outside data center. We've troubleshot the issue to where we believe it's the ...
0
votes
1
answer
287
views
In small network, how to provide ipv6 addresses in existing ipv4 subnet?
I have an ip4 192.168.0.0 subnet, with a few dozen hosts, and 6 or so servers with static IPs. I use bind 9 (On Centos 7) internally to service ip4 DNS requests. For years, I've disabled ip6, because ...
-1
votes
1
answer
143
views
How to add IPV4 range to unmanaged server
I am really inexperienced with Linux and networking.
I bought an unmanaged dedicated server running ubuntu 16.04. I am having problems with binding the ipv4/24 range with my dedicated server. How ...
0
votes
1
answer
1k
views
Ping Hyper-V Virtual Switch IPv4
I wanted an IPv4 service running on the Hyper-V host that only the VMs can access via a Virtual Switch.
Hyper-V Server 2016 (removed IPv6 public prefix)
Ethernet adapter vEthernet (Public Switch):
...
0
votes
1
answer
185
views
Generate DNS zone redirecting subdomains to IP subnet
I created DNS zone as in example below. Is there another, clean way to redirect subdomains to IP address? Maybe with bind9 $GENERATE? Can I use regex or iteration with existing DNS software? Where to ...
1
vote
4
answers
2k
views
Routing Internet Traffic through VPN tunnel
I am relatively new to the topic, so please do not mind if I ask simple (or stupid) questions.
I own a Raspberry Pi 3B and installed and configured an OpenVPN server on it.
Therefore I followed this ...
2
votes
0
answers
276
views
Kubernetes cluster not working after setting up IP forwarding
I am doing a research project and our end goal is to essentially construct a kubernetes cluster using several Raspberry Pis. I've included the fact that we are using Raspberry Pis for reference, but I ...
0
votes
2
answers
89
views
Disparity of allocated IPv4 addresses between US and China [closed]
According to IPinfo.io, United States has 1,103,394,048 IPv4 allocated addresses, while China only 342,840,576, despite having four times more population.
Is there any legal/historical/technical ...
0
votes
0
answers
215
views
Redirect IP to other IP
Good Evening everybody!
we have moved our website onto another server. Previously it was hosted on AWS. Now we are having the issue that we do not have access to our DNS settings due to some ...
1
vote
1
answer
5k
views
nginx - how to redirect depending on a range of IP addresses?
I am trying to make a site only accessible from within the local network and people from the external network will get a static page saying some other message.
This is what I am trying to do but it ...
0
votes
1
answer
493
views
How to add ipv4 capability to ipv6-only-vserver?
I have an ipv6-only-vserver and a dual stack (ipv4-ipv6) server. How do I "add" ipv4 capability to the ipv6-only-server? So it's possible to "use" it like a ipv4 server:
ssh/scp into the vserver via ...