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Questions tagged [packets]

54 questions
19
votes
3 answers

ifconfig eth0 RX dropped packets

The problem The ifconfig command shows more and more dropped packets in the RX section. So, there seem to be a problem to some packets arriving from the Internet to my server. The questions What kind of packets does this drop counter takes into…
Fox
  • 1,112
6
votes
3 answers

Tcpdump on ec2 not seeing all packets

I'm running tcpdump on an Amazon EC2 instance to monitor HTTP traffic going to Nginx (this is just a test box, the only resource is the example test page). Running tcpdump with the command # tcpdump -vn -i any port 80 shows the packets from a…
Jordan
  • 61
5
votes
2 answers

How do I fake dropped packets (or actually make them fail)?

Background One of our clients suffers from an intermittant problem with their internet where it will drop packets when a user downloads a large file (their IT is looking into the problem). I have an application consisting of a Web Server running…
Daniel James Bryars
  • 269
4
votes
1 answer

How does an Access Point handle broadcast packets from the wired side?

I have an Cisco AP 1242AG autonomous AP connected to L2 switches. Let's say I have 100 wired devices each sending 2 broadcast UDP packets per second. Obviously these packets will reach the Access Point switch port, but will the AP actually send…
atomicluis
  • 69
3
votes
1 answer

UDP. Sending speed is limited by the minimal Ethernet adapter configuration

I have 1Gbit Ethernet adapter on my computer. And I have the other computer with Ethernet adapter 100Mbit. The both in one LAN and connected through the 1Gbit switch. 1 Test: I try to send from my computer(1Gbit) to the other(100Mbit) the packets by…
Vitali Kuzniatsou
  • 33
3
votes
2 answers

Drop fragmented packets in nftables

Using iptables is it possible to block fragmented packets with this rule: iptables -A INPUT -f -j DROP But there isn't a equivalent in nftables. There is any way to do it?
rfmoz
  • 811
3
votes
1 answer

Need help understanding capturing from Wireshark?

I am having issues with my FTP servers. Connecting, sending and receiving fail sometimes, and it is not consistent. I manage to capture and filter by IP the packets, I just need pointers on what can I do from there as I don't fully understand the…
Al Pacino
  • 31
3
votes
1 answer

Percona: Got an error writing communication packets

Since a few days, two of our php-applications (symfony2) are reporting the following errors in mysql-logs: [Warning] Aborted connection 253 to db: '$appname' user: '$appname' host: 'localhost' (Got an error writing communication packets) One or two…
user196611
  • 197
2
votes
1 answer

when should I raise an alarm if I see dropped packets ( packet_in or packet_out)

I am trying to create a simple anomaly alarm detection by looking at the KPI of my Linux servers. I was wondering when should I flag an alarm if see dropped packets ( both packet_in and/or packet_out). If I take a percentage total packets…
sunny
  • 121
2
votes
1 answer

Arista switch - Forward multicast traffic from vlan to vlan on different switch ports with different subsets

I have an Arista DCS-7150S-24-R I got a cross connect from provider X into port #1 (port marked as vlan 100) I got a linux host connected to to the switch at port #2 (port marked as vlan 200) Ports are on different subnets. Port #1 receives…
Y.S
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2
votes
1 answer

Proving packets per second bottleneck?

I have a '100Mb' network connection that's currently consistently transmitting at about 20K packets/sec, irrespective of packet size in the range of 300-600 bytes. This yields an observed bandwidth of 25-98Mb. I'm constantly being told that…
user2702772
  • 125
2
votes
1 answer

Packets being routed to the wrong IP

Looked around, can't find a similar issue anywhere... I have been having some very strange and hard to explain problems on my network lately, and in my efforts to find the cause, I came across an interesting discovery, which I am struggling to…
asimovwasright
  • 145
2
votes
0 answers

Apache Instance in Private Subnet not returning packets

How can we get the Apache instance in a private subnet to work? Configuration Public subnet with 1 NAT instance Private subnet with 1 App instance Details 1. Masquerading is turned on NAT on via iptables -t nat -A POSTROUTING -j…
csi
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2
votes
0 answers

PHP-FPM slowlog and Mysql lost connection

I was having an issue with PHP-FPM and mysql. When I needed to process an input file that would generate several selects/inserts/updates for each line, it would stop after approximately 60s with message Lost connection to the server or Mysql server…
Daniel Costa
  • 337
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  • 12
2
votes
1 answer

Is there a way to explicitly set the maximum number of packets tcpdump will capture before terminating?

We have a small script that essentially does the following: A) Capture packets using tcpdump and pipe to output file. B) Run our own clean + sort script on output file. C) Display results using | sort | etc etc... So, we were wondering if there is…
anonymous-one
  • 1,098
1
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