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
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Is an IPv6-only MTA possible yet?
Has anyone had tried to run an IPv6-only SMTP engine?
Pretty much everybody with any sense has IPv6 configured for major front-end servers.
I was curious if anyone had tried to run an IPv6-only MTA ...
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How to upgrade to IPv6 for AWS EC2?
Starting yesterday, AWS is charging for IP addresses (IPv4). I would like to upgrade my EC2 instances to IPv6, but I must be missing the docs on how to do that?
I can't seem to get an EC2 instance ...
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How do clients select the DNS record from multiple DNS responses?
I have a Virtual Private Server with an IPV4 address and a range of IPV6 addresses, with the option of adding one hundred more IPV6 addresses.
Configuration:
OS:
Debian 11
IPV4:
One public Internet ...
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squid proxy - use ipv6 only for outgoing traffic
I want to set up a squid proxy to use ipv6 only for outgoing traffic.
I want the ip4 address to be totally invisible to the service I connecting to.
I don't care about fallback and lack of ipv6 ...
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How to force a server to return my IP address in IPv4 and not IPv6?
Scenario
I have a tiny PHP script on a server that echoes the IP address of any client reaching it so the address can be added to the cpanel MySQL remote hosts table via the API. I call this script ...
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2
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How to build a carrier-neutral data center?
We need to set up a very small datacenter. This needs to be carrier-neutral. What are the things we need to do to make it a carrier-neutral datacenter?
I assume that we need internet connections from ...
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Windows application listens on IPv4 but not IPv6 UDP
I have setup a Windows Server 2022 AWS EC2 instance. I installed and am testing an application that only runs on Windows.
When setting up the EC2 instance I enabled both IPv4 and IPv6. AWS requires ...
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2
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Server connection error on wifi
I have a server running debian 11 server running Mailcow. It works fine, but every now and then one of my clients will report a connection error. This connection error only appears when they use their ...
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Devices keep getting IP from previous VLAN
Some devices (printers and laptops) that are moved to another building with a different VLAN will not release the IP address assigned. I noticed this first when a laptop reported no network ...
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Why are Class E IPs in use?
According to all documentation, class E IPs - those in the range 240.0.0.0 to 255.255.255.255 - are for research purposes only and should never be assigned or used. And yet, according to a review of ...
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IIS 10 - IP Address And Domain Restrictions is denying all traffic
I have a server that has multiple sites set up on it in IIS 10.
On one of the sites, I want to allow access to a range of IP Addresses, and deny traffic to the site from all other IP Addresses.
In IIS,...
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1
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squid: Unable to allow 10.10.11.0/24 but 10.10.11.0/23 works
Im unable to make a working acl with CIDR over `/23` (squid 5.7 on Debian)
For example i got this config (working):
acl servers src 10.10.11.0/23
http_access allow servers
...
http_access deny all
...
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1
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Access subnet from another subnet
I have ipv4 address 192.168.88.130 assigned by DHCP (cannot use static IP).
I have to access devices on 192.168.20.X by changing adapter settings to static and assigning some IP from 192.168.20.X, and ...
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1
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Setting up Ubuntu vm and forgot to add a search domain
I was setting up an Ubuntu DNS server VM and accidentally forgot to add a search domain. How can I add this to my system? I set a static IP and had DHCP turned off on the machine. I am also using ...
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Use nftables to set up IPv6 NAT to IPv4
I am working on setting up a number of EC2 instances with IPv6-only networking.
A few of these servers require occasional access to IPv4-only resources controlled by third-parties.
Amazon has a blog ...
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1
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"Destination Port Unreachable" only on secondary IP of VM
An vmware VM is assigned two IPs. We can only ping one of the two IPs from VMs on the same network.
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen ...
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What makes a private IP address not routable?
I understand that private addresses such as 10.0.0.0/8,172.16.0.0/12 and 192.168.0.0/16 are not routable. However, what exactly is stopping these addresses from being routable? Do ISPs implement ACLs ...
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Dual Stack Kubernetes cluster assigning single stack IPs to pods & services
I am creating a dual stack Kubernetes cluster with kubeadm, and installing Calico. I am using the below configuration file for kubeadm:
apiVersion: kubeadm.k8s.io/v1beta3
kind: InitConfiguration
...
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1
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Internet reachable from the first subnet, not from the second, on same NIC
Hi (I hope this a the right place)
I'm working on ubuntu 18.04 with ifupdown (/etc/network/interfaces etc.), not netplan. I'm trying for several days on this difficulty.
one PC (A) with 2 cards : ...
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1
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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 ...
CommunityBot
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iptables rules - Forward/Masquerade sevices using nat table
I need to complete an exercise with iptables on a network (docker containers) configured as follows:
A router host with 2 network interfaces (eth0 <- public 10.9.0.0/24; eth1 <- lan 192.168.60....
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IIS 10 - how to block an IP range
I'm trying to figure out how to block by range on MS IIS 10, but all I can find are partial range blocks (which maybe that's all IIS can do, but I'd like to know that rather than just guess that).
So, ...
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Tuning Amazon Linux for TCP Handshake, receiving 200-300KB response, and then closing connection
I have an application which regularly creates a new TCP connection, makes a request, and then gets a just under ~300KB response before closing down the connection. Assuming that I can't redesign this ...
CommunityBot
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6
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IPv4 CIDR Ranges for Everything except RFC1918
I'm looking for a list of CIDR blocks for "The Internet", i.e. everything from 0.0.0.0 to 223.255.255.255, excluding RFC1918 address space of 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 (yes, I know ...
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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 ...
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Set IP address from VPN service (not from internet service provider) as main IP for server
I’m currently trying to get 3-4 servers for our business, situed in our office, but the main problem for us is IPv4, as in Canada, ISP charge basically ~15$/month for a single IP.
It not really a ...
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netsh command to add interface
I am working with Windows 2012 R2 Core and I having problems with setting up my NICs after they got reset.
When I run "netsh int show int" it shows bother Interfaces as Enabled and Connected.
...
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Check if IP Belongs to a CIDR
We have a list of CIDR's
1.10.10.0/24
5.154.0.0/16
5.181.219.0/24
23.90.68.0/24
31.40.214.0/24
I want to check if a IP for example : 23.90.68.56 belongs to any of the above CIDR's. If yes then we get ...
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Linux confusing MAC addresses for its IP addresses to Cisco switch?
I have multiple CentOS boxes (both Centos 7) with two different servers. These servers have 4 10GB interfaces each. They are connected to two Cisco Nexus switches. Each NIC has a different IP address, ...
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Can't add second IP adress via Netplan on Ubuntu
So I have a dedicated server for which I need a second IP adress. After ordering the adress the hoster just told me that i can now use the ip (giving me the IP, gateway and netmask). OS: Ubuntu 20.04....
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Why will Firefox resolve my domain but Chrome will not
I've been setting up a LAN DNS server using DNSMasq to forward my webserver which at the moment has https and is port-forwarded by my router. I have a domain registered which resolves fine from ...
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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. ...
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Domain connection shows as "unauthenticated"
I have seen various different questions for this problem floating around but either the circumstances arent the same or the solution doesnt work so thought i would post it to see if anybody has any ...
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Windows Server 2016 unpredictable static routes
I am configuring routes on a Windows Server 2016 machine.
I've already set up a Lan to Lan VPN as follows on a DrayTek router:
Local network: 10.23.42.96/29
Remote networks: 10.41.73.0/24, 10.41.86....
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Access IPv6 server behind router with IPv4
An IPv4 client in Germany should access an IPv6 server in the USA. This server is in a private home with a common home-router.
If it was an IPv4 server, I would just configure NAT and port forwarding ...
CommunityBot
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3
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Problems with DNS and IPv6 on Server 2012 and 2016
I manage hundreds of servers for many customers. Most are SMB segment, having 1 to 3 servers per customer max.
In past few weeks I get more and more frequent DNS errors on random domain controllers, ...
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2
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Prevent IPv6 address being exposed when connected to IPv4 only OpenVPN
I have a OpenVPN server which has IPv4 only.
I have a OpenVPN client which has IPv6 and IPv4.
While connected to the VPN the client is exposed to "IPv6 leak".
When client visits IPv6 enabled web ...
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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 ...
CommunityBot
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While using pf on FreeBSD, do I need to explicitly specify both the inet and inet6 parameters?
Suppose I have a rule like
rdr on $ext_if inet proto tcp to port https -> $inf_if port $myhttps
This is to redirect incoming TCP packets on the https port to a specific internal IP/port. This is ...
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How can i access ipv4 on ipv6 server having nat ip4 with blocked ipv4 access?
I have a nat vps, there are some restrictions set by hosting company because of many abuses, they provide nat ipv4 and dedicated ipv6 on a server, before the server was working normal like i can ping ...
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How to prevent NetScan on a dedicated server?
we have a dedicated server from Hetzner, we are using it to provie nat vps to users, the problem we are facing is that users (which we don't know how to trace) is attempting netscan due to which our ...
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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 ...
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1
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Purpose of IPv4 mapped IPv6 address
I am still confused about the purpose of IPv4 mapped IPv6 addresses and would like some enlightenment.
I have a server client pair of machines and I intend to connect them via Openvpn. The server has ...
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Channeling IPv4 packets to IPv6 packets between interfaces
How do I route packets in my machine between interfaces (See yellow arrow). Eth0 receives IPv4 packets and I will like to channel it to Eth1 which will send IPv6 packets out.Image of dual stack ...
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Split /24 IPv4 subnet into multiple /28
I would like to know if it is possible that a subnet /24 that I assigned to a dedicated server (via BGP session) can be divided into smaller subnets without the intervention of those who have access ...
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Specify different broadcast IPs for different Windows machines [closed]
I run some high-frequency trading software from home across multiple accounts. Sometimes during very volatile conditions, I run into issues with rate limits restricted by IP address.
I was assuming I ...
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Centos7 server that has no IPV6 assigned to it, can't read IPV6 ips in access log
I'm using CentOS7, nginx as a reverse proxy and apache web server. This server doesn't have IPv6 assigned to it, therefore there is no IPV6 in the NIC. This server hosts several websites.
When I check ...
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0
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IPv4 fragmentation and high speed data
Please excuse me if this has been answered before, but I couldn't easily find an answer.
My company creates high-speed measurement equipment, that produces roughly 0.7 Gigabit/second of UDP data. Each ...
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3
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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 ...
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Service bound to ipv6 on linux machine - Can I disable IPV6 and access service on my IPV4 address?
I am attempting to install Tableau Server on Ubuntu 18.04 and have the management service running on port 8850. I am unable to access the service at that port on my IPV4 address as it seems to be on ...
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