Hello all,
I am currently try to learn the linux operating system as well as some bash programming. I have come across some online course work which has been very helpful, I have been working through some assignments and since I have no teacher to ask I have come to you experts.
So the... (6 Replies)
i write a shell program and i execute that after i made a bin directiry in my home directory(i didnt give any permissions)
now i change to other directory.then i execute it bit it is saying " no such a file or directory"
can any one help me please (2 Replies)
hi and sorry for crossposting...
I have data, the first column is the date ("2011 02 03 12 45") and follow I have the measurements . What I would like to do is:
to read the data line by line and write the data of "today" in a new file and "yesterday" as well in another file, separated by... (2 Replies)
Hello,
I am processing data. In the first column there is the date ("2011 02 03 12 45") separated by space and follow I have the measurements.I have several days in one file. What I would like to do is:
to read the data line by line and write the data of "today" in a new file and "yesterday" as... (13 Replies)
Hello,
I am new to shell scripting. I have a question I would greatly appreciate any suggestions on. I am writing a ksh script that will launch bin files. The files are owned root and the application runs under root. The application administrators do not get root access. The script is intended... (1 Reply)
1. Create a directory script (project_dir.sh)
· Write a script in your home directory to create a subdirectory called “PROJECT<99>” within your home directory on the Ubantu/Linux server. <99> is your project number (e.g. 01,02,03, ... 15).
· The script must test whether... (1 Reply)
My professor has given me a couple of functions that I am to use to accomplish the task of replacing spaces in file and/or directory names with hyphens.
(i.e. A B/C D/E F and you want to rename that to A B/C D/E-F would be an example of changing the file and leaving the directories)
These are... (1 Reply)
Hi,
can someone explain how this aliases work:
alias m 'if ( \!:$ =~ *gz) set status = 1 && most \!:$ || gzcat \!:1 | most '
I mean, I know what it does, but I don't know how
- what is \!:$ and \!:1
- how do it used the && and ||
- what it does with status variable?
thanks (3 Replies)
Hello,
I am new to Linux and studying to become a Unix System Admin. I am taking a course in which I was practicing creating a bash script to ping a particular IP address. The script can be found below:
#/bin/bash
echo "Enter the IP address"
read ip
if
then
ping -c 1 $ip
if ;... (3 Replies)
Discussion started by: shah9250
3 Replies
LEARN ABOUT OSX
tc-mirred
Mirror/redirect action in tc(8) Linux Mirror/redirect action in tc(8)NAME
mirred - mirror/redirect action
SYNOPSIS
tc ... action mirred DIRECTION ACTION [ index INDEX ] dev DEVICENAME
DIRECTION := { ingress | egress }
ACTION := { mirror | redirect }
DESCRIPTION
The mirred action allows packet mirroring (copying) or redirecting (stealing) the packet it receives. Mirroring is what is sometimes
referred to as Switch Port Analyzer (SPAN) and is commonly used to analyze and/or debug flows.
OPTIONS
ingress
egress Specify the direction in which the packet shall appear on the destination interface.
mirror
redirect
Define whether the packet should be copied (mirror) or moved (redirect) to the destination interface.
index INDEX
Assign a unique ID to this action instead of letting the kernel choose one automatically. INDEX is a 32bit unsigned integer greater
than zero.
dev DEVICENAME
Specify the network interface to redirect or mirror to.
EXAMPLES
Limit ingress bandwidth on eth0 to 1mbit/s, redirect exceeding traffic to lo for debugging purposes:
# tc qdisc add dev eth0 handle ffff: ingress
# tc filter add dev eth0 parent ffff: u32
match u32 0 0
action police rate 1mbit burst 100k conform-exceed pipe
action mirred egress redirect dev lo
Mirror all incoming ICMP packets on eth0 to a dummy interface for examination with e.g. tcpdump:
# ip link add dummy0 type dummy
# ip link set dummy0 up
# tc qdisc add dev eth0 handle ffff: ingress
# tc filter add dev eth0 parent ffff: protocol ip
u32 match ip protocol 1 0xff
action mirred egress mirror dev dummy0
Using an ifb interface, it is possible to send ingress traffic through an instance of sfq:
# modprobe ifb
# ip link set ifb0 up
# tc qdisc add dev ifb0 root sfq
# tc qdisc add dev eth0 handle ffff: ingress
# tc filter add dev eth0 parent ffff: u32
match u32 0 0
action mirred egress redirect dev ifb0
SEE ALSO tc(8), tc-u32(8)iproute2 11 Jan 2015 Mirror/redirect action in tc(8)