06-15-2011
If you post your input file and sample expected output that would be more helpful.
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hi,
I have several files with data that have to be imported to a database. These files contain records with separator characters. Some records are corrupt (2 separators are missing) and I need to correct them prior to importing them into the db.
Example:
... (5 Replies)
Discussion started by: stresing
5 Replies
2. Shell Programming and Scripting
Hi,
I have many scripts in particular directory. And few of the scripts have exit 0 in second line. Now i wanted to list out the scripts name which has the exit 0 in its second line
I tried many options , but i can not get the filename along with the nth line pattern match :mad:. Can anyone... (14 Replies)
Discussion started by: puni
14 Replies
3. UNIX for Dummies Questions & Answers
I have several files (around 50) that have the similar format. I need to extract the 5th line from every file and output that into a text file. So far, I have been able to figure out how to do it for a single file:
$ awk 'NR==5' text1.txt > results.txt
OR
$ sed -n '5p' text1.txt > results.txt... (6 Replies)
Discussion started by: oriqin
6 Replies
4. Shell Programming and Scripting
Please help me how can I display every nth field present in a "|" delimited file.
Ex: If a have a file with data as a|b|c|d|e|f|g|h|k|l|m|n
I want to display every 3rd feild which means the output should be
c
f
k
n
Please help me. (1 Reply)
Discussion started by: ngkumar
1 Replies
5. UNIX for Dummies Questions & Answers
Hi ,
I want to print the nth and n+1 lines from a file once it gets a pattern match.
For eg:
aaa
bbb
ccc
ddd
gh
jjjj
If I find a match for bbb then I need to print bbb as well as 3rd and 4th line from the match.. Please help..Is it possible to get a command using sed :) (6 Replies)
Discussion started by: saj
6 Replies
6. Answers to Frequently Asked Questions
I see lot of request posted in internet to find out the day of nth week in a Month.
example:
what is the date of 3rd Sunday in October
What is the date of 2nd Friday in June 2012
what is the date of 4th Saturday in January 2011..etc..
The below shell script is used to find out the... (1 Reply)
Discussion started by: itkamaraj
1 Replies
7. Shell Programming and Scripting
Hi all,
I'm trying to create a sed command to get the Nth instance of an XML tag in a string, but thus far I can only ever seem to get the last one.
Given an XML string:
<Wrap><GrayLevel>a</GrayLevel><GrayLevel>b</GrayLevel></Wrap>
I tried to do this on the command line to get each... (7 Replies)
Discussion started by: Zel2008
7 Replies
8. Shell Programming and Scripting
Hi All,
I have sample of listing as following
Database 2 entry:
Database alias = PXRES
Database name = PXRES
Local database directory = /db2/data1/db2phnx
Database release level = d.00
Comment ... (3 Replies)
Discussion started by: ckwan
3 Replies
9. Shell Programming and Scripting
I have a situation where a file "config.txt" looks like this
Servername:
OS:
Serername:
OS:
Servername:
OS:
....
....
...
Servername:
OS:
looking for the sed syntax to replace the "Nth" occurrence of Servername (i would apply the same logic to OS as well), want to replace the Nth... (4 Replies)
Discussion started by: alldbest
4 Replies
10. AIX
Please help me
print nth line after match
awk or sed one line command. (3 Replies)
Discussion started by: sushma123
3 Replies
Packet sample action in tc(8) Linux Packet sample action in tc(8)
NAME
sample - packet sampling tc action
SYNOPSIS
tc ... action sample rate RATE group GROUP [ trunc SIZE ] [ index INDEX ]
tc ... action sample index INDEX
DESCRIPTION
The sample action allows sampling packets matching classifier.
The packets are chosen randomly according to the rate parameter, and are sampled using the psample generic netlink channel. The user can
also specify packet truncation to save user-kernel traffic. Each sample includes some informative metadata about the original packet, which
is sent using netlink attributes, alongside the original packet data.
The user can either specify the sample action parameters as presented in the first form above, or use an existing sample action using its
index, as presented in the second form.
SAMPLED PACKETS METADATA FIELDS
The metadata are delivered to userspace applications using the psample generic netlink channel, where each sample includes the following
netlink attributes:
PSAMPLE_ATTR_IIFINDEX
The input interface index of the packet, if there is one.
PSAMPLE_ATTR_OIFINDEX
The output interface index of the packet. This field is not relevant on ingress sampling
PSAMPLE_ATTR_ORIGSIZE
The size of the original packet (before truncation)
PSAMPLE_ATTR_SAMPLE_GROUP
The psample group the packet was sent to
PSAMPLE_ATTR_GROUP_SEQ
A sequence number of the sampled packet. This number is incremented with each sampled packet of the current psample group
PSAMPLE_ATTR_SAMPLE_RATE
The rate the packet was sampled with
OPTIONS
rate RATE
The packet sample rate. RATE is the expected ratio between observed packets and sampled packets. For example, RATE of 100 will lead
to an average of one sampled packet out of every 100 observed.
trunc SIZE
Upon set, defines the maximum size of the sampled packets, and causes truncation if needed
group GROUP
The psample group the packet will be sent to. The psample module defines the concept of groups, which allows the user to match spe-
cific sampled packets in the case of multiple sampling rules, thus identify only the packets that came from a specific rule.
index INDEX
Is a unique ID for an action. When creating new action instance, this parameter allows to set the new action index. When using
existing action, this parameter allows to specify the existing action index. The index must 32bit unsigned integer greater than
zero.
EXAMPLES
Sample one of every 100 packets flowing into interface eth0 to psample group 12:
tc qdisc add dev eth0 handle ffff: ingress
tc filter add dev eth0 parent ffff: matchall
action sample rate 100 group 12 index 19
Use the same action instance to sample eth1 too:
tc qdisc add dev eth1 handle ffff: ingress
tc filter add dev eth1 parent ffff: matchall
action sample index 19
SEE ALSO
tc(8), tc-matchall(8) psample(1)
iproute2 31 Jan 2017 Packet sample action in tc(8)