3
votes
0answers
69 views

TCP packet being retransmitted 7 times when sysctl tcp_retries1 is set to 3 - why?

Ubuntu 12.04 I am trying to better understand how many times TCP will attempt to retransmit a packet when it does not receive confirmation the destination received it. After reading the tcp man page ...
0
votes
0answers
40 views

Tomcat fails to return syn requests to F5

I have an F5 LTM sitting in front of two tomcat servers which host 4 applications. When I initially create the pools and add the members to the LTM I can hit all applications. This is the weird part, ...
1
vote
1answer
78 views

Prevent Linux from processing incoming ICMP Host unreachable packets

I have a test setup with one host on a network (10.1.0.0/16) talking via TCP to another one on another network (10.2.0.0/16) and a gateway in the middle. Sometimes, the TCP connection is lost and ...
0
votes
0answers
42 views

Linux + OpenVPN + SNAT + Failure on client grab the reply to it's own generated traffic

Ok, I'm really desesperate I need to release an openvpn deploy to get rid of a dying server. On the subject: I installed OpenVPN with a routed interface (tun0) into a server with a public IP + 3 ...
4
votes
1answer
1k views

Too many TCP connections causes disconnections

I have a game server which runs with TCP connections. Server disconnects users randomly. I think its related with TCP settings of server. In local development environment written code can handle ...
0
votes
1answer
86 views

What process does 'own' socket in 'Time Wait' state?

Main question I see following line in netstat. Does it means this socket doesn't belong to any process? #>netstat -tpn|grep TIME_WAIT| head -1 tcp 0 0 ::ffff:127.0.0.1:5555 ...
0
votes
1answer
79 views

How to run Different congestion control algorithms in FEDORA 17?

I need to use different congestion control algorithms for tcp flow. How can I continue using those flow congestion algorithms from Fedora 11 in Fedora 17?
0
votes
2answers
105 views

Testing -How to generate limited rate tcp streams?

Running with ubuntu. I have clients that has limited transfer rate. I need to test my server to see in how much clinets with limited transfer rate it support? Is there any utility that allow me to ...
-1
votes
3answers
3k views

tcp handshake failed.client send rst (after syn-ack). can any one advice?

topology: 2 linux computer connected directly . no iptables rules (except - iptables -A OUTPUT -p tcp -j NFQUEUE ) no firewall. route is defined as - "route add default dev eth0" on the second one ...
0
votes
1answer
231 views

server dosnt produce syn-ack

I have a small program that take packets from the nfqueue . change the ip.dst to my server dst (and ttl), recalc checksum and return the packet to the nfqueue. The server and the client are linux and ...
0
votes
1answer
181 views

TCP handshake ok, then the client isn't receiving any packets from the server

Topology: Client ----- Intermediate Device ----- Server Client: win7 Intermediate Device: unknown Server: CentOS 5.8 The problem occurs when the client and server are trying to establish a SSL ...
1
vote
3answers
3k views

How to formulate IP forwarding rule using iptables

I have two Systems A and B. A is a TCP Client and sends a message to TCP Server on B. ------------------ -------------------------- System A System B ...
1
vote
1answer
214 views

Server behind DMZ firewall won't respond

I have a DMZ server set up to forward specific ports to a couple of machines. The intended behavior is for me to send a request to the DMZ on a specific port, and have the machine that's inaccessible ...
3
votes
1answer
3k views

Kill Tcp Connection

Greeting, I am testing application on linux, and we have a bug related to the database connection, since the database connection cannnot be restarted and it's on a remote machine, I would like to ...
0
votes
1answer
511 views

Improving TCP performance over a network with small packet loss

I’m trying to improve my TCP throughput over a “high delay network”, with some packet drops, between Linux machines. I set tcp_mem, tcp_wmem and tcp_rmem to “8192 20530752 20530752”. I set rmem_max, ...
8
votes
1answer
23k views

What does “net_ratelimit: 44 callbacks suppressed” mean on a linux based router?

I'm trying to tune Snort performance on a Debian based router. I was seeing stuff like: snort packet recv contents failure: No buffer space available So I upped the buffers to 8M and when that ...
2
votes
3answers
1k views

How to enable TCP for DNS resolution?

I've been doing some reading about this, according to what I understood this is possible, but HOW??, I know UDP is much much better for DNS resolution but because of so many issues an restrictions, ...
0
votes
0answers
76 views

tcpproxy tool showing weird malloc errors

I'm using tcpproxy-2.0.0-beta15 tool to proxy/PAT some remote connections and I use the config file for the tool. Everything was fine until it crashed and when I tried to start, I get this, ...
3
votes
2answers
3k views

query TCP buffer sizes for a socket on linux

Is there any way to lookup the send/receive buffer sizes for TCP sockets? I've poked around with both netstat and ss, as well as the raw /proc/net/tcp. Lots of goodies there, including the counts of ...