The tag has no wiki summary.

learn more… | top users | synonyms

2
votes
1answer
40 views

macos - local port redirection using pfctl and syntax errors

I am running MacOS(really BSD), and I want to redirect certain traffic over an ssh tunnel using a a local forward. Seems easy enough, but I am repeatedly blocked by the ambiguous "/etc/pf.conf:29: ...
1
vote
1answer
70 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 ...
0
votes
0answers
19 views

All packets after the first one on tun0 are dropped

I'm trying to run the Aventail VPN 10.7.1.449, and it doesn't work since every packet after the first one is getting dropped: tun0 Link encap:UNSPEC HWaddr ...
1
vote
1answer
33 views

How does Linux prevent applications from sending more packets than the link can handle without dropping packets?

I couldn't make the question any clearer so here's an example scenario: Given a Linux machine connected to an IP network through a physical interface of bandwidth 10Mbps (or a higher speed interface ...
0
votes
1answer
44 views

Smallest packet sniffer for an embedded device?

Are there tiny packet sniffers out there? I'm looking for something that can be compiled for a embedded device with very limited space. I thought of tcpdump but a dynamically linked and stripped ...
3
votes
0answers
93 views

iptables: using “conntrack” and “recent” modules to block unsolicited packets

When I only allow RELATED and ESTABLISHED packets, and DROP everything else, my firewall rules work perfectly and I have no problems: ### VARIANT A -A INPUT -i wlan0 -m conntrack --ctstate ...
1
vote
1answer
246 views

record contents of packets dropped in iptables

I'm trying to find a way to record the entire contents of packets (possibly with tcpdump) that have been dropped according to rules in iptables. At present, I have a rule to log these packets (with a ...
0
votes
1answer
103 views

Received DUP when using ping. What should I do?

I was pinging Google last night and one of them came back as DUP(!). I did some reading and I found this in the man pages on ping(8): Damaged packets are obviously serious cause for alarm and ...
1
vote
2answers
152 views

How can I debug traffic on a switched network with Wireshark?

I have an IP phone on my home network that I am trying to call using SIP from outside of my home network. I have port forwarding setup, but the phone is responding with a SIP 404 message. All the ...
1
vote
3answers
79 views

Is it bad to select remember me option in the browsers of a compromised machine?

I was reading an article on how to sniff network packets. (of course for knowledge purposes only). I came across these particular lines. For instance, say I was sniffing traffic on the network, ...
0
votes
1answer
60 views

Simple iptables filter rule for 101/8 block not working

I run a webserver that caters to an entirely local crowd, so to keep hacking attempts to a minimum, I have inserted a bunch of international IP-blocking rules into my iptables, but my filters don't ...
2
votes
1answer
66 views

How might I log my Internet traffic, grouped by IP address/hostname, port, etc?

While I'm going to be switching to a slightly saner plan soon, being stuck on a 5GB monthly bandwidth cap has made me very data-conscious, and I'm looking for a way to log my Internet usage in such a ...
2
votes
2answers
4k views

Packet loss with RX error packets

I am seeing packet loss from all my blade servers within the HP Blade C7000 enclosure. # ping 192.168.2.140 PING 192.168.2.140 (192.168.2.140) 56(84) bytes of data. 64 bytes from 192.168.2.140: ...
0
votes
1answer
111 views

How to log all udp packets from port N in readable format?

How to log into file all udp packets (in and out) from port N in readable format (capture packet type (time stamp, name of error if one happens or message type, data size, data))?
2
votes
2answers
354 views

Shell script to wait for a packet from a certain port

I want to start my minecraft server when someone tries to connect to it on port 25565. I have a plugin for the server which shuts it down after x amount of minutes without players online. With a shell ...
3
votes
1answer
596 views

how to intercept IP packets on linux

I am trying to achieve this goal on Linux (not sure if it is possible and how if so): I need to write a program to intercept all IP packets on an interface, and deliver this packet to a specific set ...
0
votes
1answer
92 views

How do I verify that the Linux kernel is not freezing when uploading or downloading large data over the ethernet interface?

How to verify if the Linux kernel is doing what it's saying for network interfaces? I have one network interface eth0 which has hardware support to do 1GB full-duplex. I have prepared 2 box. Now ...
2
votes
2answers
120 views

Tshark not running via gdb

I have successfully installed wireshark on centos 6.4 I can run the command tshark it works perfectly fine. I want to run gdb so that I want to learn how it decodes tcp and udp packet as I am writing ...
1
vote
1answer
129 views

Wireshark packet dissection codes?

Hi all we have a system which could capture packets accordingly. The only problem now we need some codes on how to interpret the packet just like how wireshark does it so well. Anyplace we can get ...
1
vote
1answer
698 views

How do I check if I have packet socket support enabled in my distro's kernel?

How do I check that packet socket support has been compiled into my kernel? I'm running Crunchbang, a Debian-based distribution.
1
vote
3answers
361 views

Packet analyzer to intercept and filter incoming traffic before any client app

I am curious if most Linux distros make it possible to intercept incoming network traffic as soon as it enters the system and filter its content based on some rules before any other client can use it ...
2
votes
1answer
672 views

Why is a echo-request ping packet 84 bytes in the log of iptables?

When I log the length of a echo-request packet, iptables -A OUTPUT -p icmp -m icmp --icmp-type 8 -j LOG I saw the length was LEN=84, but in wireshark, the captured packet size was 0x60, why does it ...