What is the TC command?

What is the TC command?

Tc is used to configure Traffic Control in the Linux kernel. Traffic Control consists of the following: SHAPING When traffic is shaped, its rate of transmission is under control. Shaping may be more than lowering the available bandwidth – it is also used to smooth out bursts in traffic for better network behaviour.

How do I add a delay to a network in Linux?

A few examples of how to do so are:

  1. Add 10ms of delay to every packet transmitted on eth0: $ tc qdisc add dev eth0 root netem delay 10ms.
  2. Add 10ms of delay and 20ms of jitter to every packet bridged by br0: $ tc qdisc add dev br0 root netem delay 10ms 20ms.

How do I drop a packet in Linux?

There are two simple ways to randomly drop packets on a Linux computer: using tc, the program dedicated for controlling traffic; and using iptables, the built-in firewall. A good description of using tc to drop packets (as well as other features) is available via the Linux Foundation site.

What is Linux NetEm?

NetEm is an enhancement of the Linux traffic control facilities that allow to add delay, packet loss, duplication and more other characteristics to packets outgoing from a selected network interface.

How do you add a delay in ping?

Use PING to create a time delay: Create a delay of 1 or more seconds by pinging the loopback address (127.0. 0.1) multiple times.

How do I simulate network disconnect?

Simulating a hard-down or node failure is fairly easy. All you have to do is turn off the node itself to verify how the system responds (system reconvergence). If high availability is enabled, a secondary/standby node will immediately take over and become the active node, servicing user requests.

How do I see packets in Linux?

Displaying show dropped packets per interface on Linux using the netstat

  1. To display summary statistics for each protocol, run: netstat -s.
  2. Show tcp stats. netstat –statistics –tcp.
  3. Display udp stats. netstat –statistics –udp.
  4. Building dropwatch.