Tagged Questions

1
vote
0answers
45 views

TCP 443 Connection goes into server but never reaches Apache2 (Passenger)

We have some weird problems, when external servers try to connect to our Website on Port 443(TCP) which is an Apache2+Passenger and a Rails Application. The problem only happens rarely. I started to ...
3
votes
1answer
61 views

Does a growing number of TIME_WAIT connections affect server performance?

I have 2 servers, both running RHEL 6, one for Apache 2.2 and one for memcached (memcached-1.4.4-3). I noticed an increase in the number of TIME_WAIT connections on the Apache server netstat -n | ...
2
votes
0answers
184 views

Varnish running out of open ports, lots of SYN_SENT connections

Recently we've been experiencing issues with our Varnish (3x) -> Apache (3x) setup, resulting in a huge spike in SYN_SENT connections. The spike itself is due to the amount of new traffic hitting the ...
1
vote
0answers
82 views

Website latency and bad tcp packets

I have multiple websites hosted on a Linode VPS and I'm having an issue with one of them: every page that I try to load has about 10 seconds latency. Apache logs are clean and the other websites on ...
0
votes
1answer
74 views

Port scanning from localhost

I see lot of tcp connections on different ports on my server with 'TIME_WAIT' status. Just simple port scan, but i cant see ip address of this bastard because connections is going from my nginx. Can ...
0
votes
2answers
137 views

How do I print the x-forwared-for value in apache?

We have a aws load balancer. The load balancer uses the TCP connections 443 to encrypt the data. Since the load balancer encrypts the IP of the client, in our apache log file we can see only the IP ...
0
votes
0answers
41 views

ldap_search hanging in poll

My ldap_search call is hanging in a poll statement. The relevant gdb backtrace of my tcp connection is as follows. (gdb) bt #0 0x00002ba073e16eff in poll () from /lib64/libc.so.6 #1 ...
2
votes
2answers
141 views

Apache not processing new requests without reaching max_client value.With many idle children

we are facing a problem,that new requests are not processed even if apache hasn't reached its max_client setting. Max_client is set to 800 max_spare server is 36 min_spare server is 35 ...
11
votes
7answers
4k views

Apache Tomcat chokes after 300 connections

We have an apache webserver in front of Tomcat hosted on EC2, instance type is extra large with 34GB memory. Our application deals with lot of external webservices and we have a very lousy external ...
2
votes
1answer
1k views

apache webserver unresponsible with server-status showing all child processes waiting for connection

My setup: i have 3 nearly identical webserver machines serving the same high loaded dynamic website with simple load balancing over dns. The service has been working for over two ears with the same ...
1
vote
0answers
209 views

LDAP request seems to hang at repeating 125 byte packet, and TCP connection does not close

I've rewritten this question to focus on a specific part. Originally titled "Apache hangs or quits, but keeps TCP sockets open and won't accept connections" Problem Problem is a website (Moodle) ...
0
votes
1answer
185 views

Finding the so_sndbuf of a running process

I'm wondering if there's any way to find the tcp so_sndbuf of an actively running process (such as apache or nginx). I know that tcp_wmem sets the default value, but I'm not sure if the server ...
0
votes
2answers
190 views

Is an Apache use TCP port on each connection?

Our system admin said "Apache use a TCP port on each connection" so A server can serve 65534 (MAX) simultaneously. is it Right? I think Apache use only 80 or 443. But , he use many file descriptor ...
0
votes
1answer
2k views

All connections from this network get stuck in SYN_RECV state, connections from my home or phone properly get ESTABLISHED

My server (a linode VPS) suddenly started to timeout on every request yesterday. I'm pretty inexperienced in networking and would love to learn a process for debugging these connectivity issues. ...
2
votes
1answer
748 views

Why do I see an IP packet with size 2960, way above the MTU setting of 1500 on the interface and it gets through?

I am analyzing traffic between a client and a Linux webserver running on a HP blade server, the client sometimes gets stuck waiting for more data when the webserver has closed the connection. The ...
1
vote
2answers
332 views

Monitor total bytes sent over TCP connection by ip address

Newbie sys-admin here, On my website, users download a 50MB file. I want to be able to know whether the download has completed for them so that I can run a bash script. I'm on a LAMP stack, and the ...
2
votes
4answers
1k views

Strange 3-second tcp connection latencies (Linux, HTTP)

Our webservers with static content are experiencing strange 3 second latencies occasionally. Typically, an ApacheBench run (> 10000 requests, concurrency 1 or 40, no difference, but keepalive off) ...
5
votes
1answer
455 views

What is the meaning of “Treason Uncloaked” in Linux?

On a Linux Apache server, from time to time, there are messages saying TCP: Treason uncloaked!. There are previous questions on ServerFault explaining the fixes for this issue. However does anyone ...
3
votes
2answers
4k views

Should I use TCP or UDP to run a web server

I have just installed Apache web server on my computer. I have managed to use it locally (I can open index.php from my computer using my web browser). But I would like to make my web site available ...
3
votes
2answers
2k views

dmesg SYN flood on 80 sysctl -p

I am getting a synflood on my server port 80 and i cannot stop it. first i got tables full then i disabled iptables to find out that its a synflood netstat -n | grep :80 |wc -l #returns 1300 - 2000 ...
1
vote
1answer
1k views

Apache Timeout directive not working?

I have configured /etc/apache2/apache2.conf with Timeout 5 instead of the default 300. So I understand it should close an incoming connection after 5 seconds of inactivity. But I make a telnet ...