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Questions tagged [ipv4]

Use the ipv4 tag ONLY if the nature of your question specifically involves IPv4 addresses or networking -- often in contrast to IPv6. Most networking currently involves IPv4 addresses, so you should NOT include this tag with every networking question.

14
votes
2answers
43k 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 ...
6
votes
3answers
24k 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 Password:...
3
votes
1answer
6k 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: ...
1
vote
1answer
221 views

does :::80 in netstat output means only ipv6 or ipv6+ipv4?

If I am listening on :::80, is it listening on all ipv6 or all ipv6+ipv4? This is my netstat -tln: tcp 0 0 :::8080 :::*
0
votes
3answers
162 views

Find local processes starting TCP connections

With tcpdump I see many SYN packets ... and source IP is Localhost. I wish to find which processes are trying to connect. Note the connections don't reach ESTABLISHED state, they seems to be random ...
0
votes
1answer
1k views

How does Linux choose between default gateways?

I have a computer with two NICS, one eth one wlan. wlan is on 10.0.0.0/24 eth is on 192.168.0.0/16 Kernel routing table is: $ route -n Kernel IP routing table Destination Gateway ...