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0answers
20 views

I am redirected to a router that is not part of my provider's configuration [closed]

Whenever I try to access a website with a .com domain it shows the 'unable to connect page' but when I access a site with my country's domain I get redirected to a Tenda 11N wireless router. I ...
0
votes
1answer
25 views

IPV4 getting removed after restart CentOS machines

I have CentOS machines (both 6.x and 7.1) and whenever I reboot them, automatically IPV6 is assigned to them and IPV4 is lost. Any idea why it is happening and how to prevent it? I Could not ...
3
votes
2answers
42 views

Fedora Core 4 won't get an IPV4 address

I have a fedora core machine, and it is picking up an IPV6 address, but not an IPV4 address. I have done dhclient -r eth0 but the ipv4 address has not come. I have reset the port using ifconfig, but ...
0
votes
0answers
113 views

Changing the port letsencrypt tries to connect on

So, one of my servers is behind NAT, and since there is already a publicly accessible apache server going on my LAN, I decided to access it from the outside with different ports, and remap them to the ...
2
votes
3answers
366 views

Validating IP addresses (IPv4 and IPv6)

Quite simply I'd like to verify that a string represents a valid IP address in a bash script. I think like many others I've fallen into the pitfall of trying to do this with a regular expression; ...
3
votes
0answers
129 views

curl request to IPv6 localhost gets stuck

A docker container of mine exposes a HTTP interface on port 8500, which is mapped to host port 8500. It is not IPv6 enabled. This still means, I should be able to access it at localhost:8500. IPv6 ...
2
votes
2answers
78 views

Retrieve IPv6 address of website using terminal

Both the nslookup and host commands return IPv4 addresses only. How can i retrieve the IPv6 address of a website using the terminal? (I have googled around, unfortunately I couldn't find anything ...
0
votes
1answer
57 views

According to socket statistics Apache listens only on IPv6, but actually serves IPv4 as well

ss -lnp in server shows following information: # ss -lnp Recv-Q Send-Q Local Address:Port ...
2
votes
1answer
71 views

What's ndisc_cache?

Suppose I want to use : $ ip ntable show dev eth0 inet arp_cache dev eth0 refcnt 4 reachable 20744 base_reachable 30000 retrans 1000 gc_stale 60000 delay_probe 5000 queue 31 ...
1
vote
2answers
60 views

Execute Perl commands from a specific IP?

I have a Debian Jessie 8 server with three unique IPv4 IPs. I connect to the server from Windows 7 via Putty. I can open three Putty windows using each of the three IPs. I am trying to execute a Perl ...
2
votes
1answer
494 views

NAT box with multiple internal and external interfaces

Similar questions have been asked before but my setup is a little different and the solutions to those questions are not working. A have a CentOS 6 server running iptables with 5 interfaces: eth0: ...
2
votes
0answers
433 views

Force IPv4 over IPv6 only for certain addresses

I'm currently running Debian 8 and I'm trying to force applications like Google Chrome to use IPv4 over IPv6 only for certain sites. My ISP natively offers IPv6 and it's amazing on all websites that ...
1
vote
1answer
136 views

How does Debian select or prioritize IPv4 and IPv6 connections?

I'm going to explain my question with an example. I have two servers, A and B, both runs Debian 7.8, both have dual-stack connection to the Internet (I don't know if it matters but they even have the ...
0
votes
1answer
464 views

IPv4 broadcast routing in Linux

I have a server with three network interfaces- loopback interface lo and two physical network interfaces eth0 and eth1: 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN ...
1
vote
0answers
157 views

How does s_client turn ip6-localhost into 127.0.0.1?

When I use openssl s_client and ask it to connect to ip6-localhost it actually connects to 127.0.0.1 instead of ::1. This is what I see on both Ubuntu and Debian: $ strace -e connect openssl ...
1
vote
1answer
200 views

IPv4 goes offline several times per hour on headless remote server, IPv6 unaffected

On my Ubuntu 14.04.2 server IPv4 goes offline several times per hour (one to four times I've seen, but at no particular minute per hour or so). My hoster insists that the problem is on the ...
2
votes
2answers
5k views

Installing vsftpd - 500 OOPS: could not bind listening IPv4 socket?

I have to set up a FTP server on my machine. I have installed vsftpd using the command: sudo apt-get install vsftpd I then edited the configuration file vsftpd.conf in the location /etc. The file ...
0
votes
0answers
244 views

Flow of ipv4 over ipv6 tunnel

Re-posting my question from stackoverflow I am trying to achieve flow of ipv4 packets over ipv6 tunnel between 2 machines. Initially i had the following setup Linux1 eth0 ...
2
votes
2answers
3k views

Can I prevent a default route being added when bringing up an interface?

I have a system with two NICs on it. This machine, and a few accompanying devices will be moved and attached to different LANs or sometimes it'll be using dial-up. eth0: - 10.x.x.x address space - ...
1
vote
0answers
244 views

Arch Linux sudden wifi disconnects and unable to reconnect

I have a problem with my wifi internet connection that is secured by WPA. I have moved to a new location. I had set up a working internect connection but lost the connection after about an hour and ...
0
votes
0answers
327 views

Iptables and Ip6tables redirect traffic

I want to deny all the network traffic and just allow a few ports and redirect them through tor or the socket I have set in /etc/tor/torrc, where tor binds to. And I am currently setting up these ...
7
votes
2answers
10k views

netstat — why are IPv4 daemons listening to ports listed only in -A inet6?

I have a computer with: Linux superhost 3.2.0-4-amd64 #1 SMP Debian 3.2.60-1+deb7u3 x86_64 GNU/Linux It runs Apache on port 80 on all interfaces, and it does not show up in netstat -planA inet, ...
30
votes
4answers
7k views

Can TCP provide more than 65535 ports?

Is it possible to setup a Linux system so that it provides more than 65,535 ports? The intent would be to have more than 65k daemons listening on a given system. Clearly there are ports being used ...
1
vote
1answer
413 views

Define specific TTL for each interfaces

After some research, I was wondering if it was possible to define a TTL by interface as I can the Hop Limit definition in ipv6. To change the TTL in IPv4, I can change the file ...
2
votes
0answers
105 views

Allow internet access to public subnet

I'm running ESXi and received a public subnet from Hertzner.de . I've setup everything by using a 'router'-vm and different client-vm's. These client VM's can access the internet through the router-vm ...
0
votes
1answer
122 views

What is the pathname (the directory and file name) of the configuration file used for the DHCP client (not the server!)

(This question refers to the IPv4 client, not the IPv6 client.) (Hint: configuration files are kept under the directory /etc.) It is for a school assignment. I have to use man pages to find it. I ...
4
votes
1answer
1k views

Fedora 18 guest in VirtualBox 4.2: How to assign static IPv4 address to guest regardless of active ethernet interface on host

I have a Ubuntu 13.04 host running VirtualBox 4.2.12. This host has both a wired and a wireless network interface, but only one of which would usually be active at any given time. For example, at home ...
3
votes
2answers
11k views

SSH login via IPv6 successfull while using IPv4 to the same host yields “Permission denied”

I'm currently stumped by a strange problem… I have a dual stack host to which I want to SSH. If I connect via IPv6 everything works like expected datenwolf@foo ~/ > ssh -6 bar.example.com ...
1
vote
1answer
2k views

How can I disable IPv6 in custom built embedded setup

I have an embedded system built using buildroot. I have had a number of network issues, one of which is that my machine cannot see its gateway despite it being on the same subnet. I have tried using ...
1
vote
1answer
451 views

Add ipv4 support to CentOS 6.3

I've installed two identical versions of CentOS using VirtualBox. The first instance works fine and has ipv4 configuration automatically working, but the second instance doesn't; it only comes with ...
7
votes
1answer
664 views

Detect other machine's address in link local?

I have two machines connected in link local IPv4 over a CAT6 cable. Is there a way from host1 that I can determine host2's IPv4 address? I'm on an Debian-derivative running kernel 3.2.0-34-generic.
2
votes
2answers
890 views

How to configure dhcpd to register ipv4 with bind while having static ipv6 addresses?

I have IPv6 configured on my local network via radvd; it advertises a routable IPv6 block, that all the machines auto-configure.s I have IPv4 assigned to a NAT'd block via dhcpd and that updates ...
2
votes
0answers
416 views

openBSD static ip can't connect

I have set /etc/hostname.msk0 to inet 192.168.1.102 255.255.255.0 NONE and /etc/mygate to 192.168.1.1 but still can't ping the router (192.168.1.1) do I need to configure dns to ping ? ...
8
votes
2answers
62k views

Static IPv4 & IPv6 configuration on CentOS 6.2

I try to configure static IPv4 & IPv6 configuration on CentOS 6.2. The configuration below works perfectly : # ifconfig eth0 x.x.x.x/29 # route add defalt gw x.x.x.y # ip addr add dev eth0 ...
2
votes
2answers
261 views

IPv6 NDP timer problem

Need to change Fedora Linux's IPv6 stack for NDP DAD timer changes. How to locate the Fedora's IPv6 and IPv4 stack in Fedora distribution dvd/site so that, we can recompile and generate new stack ?
5
votes
2answers
22k views

Two interfaces, two addresses, two gateways?

I have a system that has two network interfaces with different IP adresses, both of which are in the public address range (albeit via NAT in the case of the first one) and both of which have different ...