Sponsored Content
Top Forums Shell Programming and Scripting Using sed to extract line of a file Post 303034865 by RudiC on Wednesday 8th of May 2019 09:04:51 AM
Old 05-08-2019
How about
Code:
awk '/^ *interface/ {IF = $0} /helper/ {if (IF) print IF; IF = ""; print}' file
interface Vlan3
 ip helper-address 192.168.228.188
 ip helper-address 192.168.97.199
 ip helper-address 192.168.133.140
 ip helper-address 192.168.152.194
interface Vlan5
 ip helper-address 192.168.228.188
 ip helper-address 192.168.97.199
 ip helper-address 192.168.133.140
 ip helper-address 192.168.152.194

EDIT: or, with sed,

Code:
sed -n '/^ *interface/ { :L1; x; /helper/ p; n; }; :L2; /helper/ {H; n; bL2; }; $ bL1;' file


Last edited by RudiC; 05-08-2019 at 10:34 AM..
This User Gave Thanks to RudiC For This Post:
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Extract a line from a file using the line number

I have a shell script and want to assign a value to a variable. The value is the line exctrated from a file using the line number. The line number it is not fix, and could change any time. I have tried sed, awk, head .. See my script # Get randome line number from the file #selectedline = `awk... (1 Reply)
Discussion started by: zambo
1 Replies

2. Shell Programming and Scripting

extract file extension using sed

Hi, how can i extract file extension using sed? for e.g., if a file name is abc.txt then how can i get "txt" (after .) Thanks praveen (7 Replies)
Discussion started by: r_praveenk
7 Replies

3. Shell Programming and Scripting

extract a line from a file using the line number

Hello, I am having trouble extracting a specific line from a file when the line number is known. My first attempt involved grep -n 'hi' (the word 'hi will always be there) to get the line number before the line that I actually want (line 4). Extra Notes: -I am working in a bash script. -The... (7 Replies)
Discussion started by: grandtheftander
7 Replies

4. UNIX for Dummies Questions & Answers

Using sed to extract a substring at end of line

This is the line that I am using: sed 's/^*\({3}*$\)/\1 /' <test.txt >results.txt and suppose that test.txt contains the following lines: http://www.example.com/200904/AUS.txt http://www.example.com/200903/_RUS.txt http://www.example.com/200902/.FRA.txt What I expected to see in results.txt... (6 Replies)
Discussion started by: figaro
6 Replies

5. Shell Programming and Scripting

get the fifth line of a text file into a shell script and trim the line to extract a WORD

FOLKS , i have a text file that is generated automatically of an another korn shell script, i want to bring in the fifth line of the text file in to my korn shell script and look for a particular word in the line . Can you all share some thoughts on this one. thanks... Venu (3 Replies)
Discussion started by: venu
3 Replies

6. Shell Programming and Scripting

Extract a number from a line in a file and sed in another copied file

Dear all, I am trying to extract a number from a line in one file (task 1), duplicate another file (task 2) and replace all instances of the strings 300, in duplicated with the extracted number (task 3). Here is what I have tried so far: for ((k=1;k<4;k++)); do temp=`sed -n "${k}p"... (2 Replies)
Discussion started by: mnaqvi
2 Replies

7. Shell Programming and Scripting

extract a line from a file by line number

Hi guys, does anyone know how to extract(grep) a line from the file, if I know the line number? Thanks a lot. (9 Replies)
Discussion started by: aoussenko
9 Replies

8. Shell Programming and Scripting

HELP: Shell Script to read a Log file line by line and extract Info based on KEYWORDS matching

I have a LOG file which looks like this Import started at: Mon Jul 23 02:13:01 EDT 2012 Initialization completed in 2.146 seconds. -------------------------------------------------------------------------------- -- Import summary for Import item: PolicyInformation... (8 Replies)
Discussion started by: biztank
8 Replies

9. Shell Programming and Scripting

sed or awk, cut, to extract specific data from line

Hi guys, I have been trying to do this, but... no luck so maybe you can help me. I have a line like this: Total Handled, Received, on queue Input Mgs: 140 / 14 => 0 I need to, get the number after the / until the =, to get only 14 . Any help is greatly appreciated. Thanks, (4 Replies)
Discussion started by: ocramas
4 Replies

10. Shell Programming and Scripting

Perl to extract information from a file line by line

In the below perl code I am using tags within each line to extract certain information. The tags that are used are: STB >0.8 is STRAND BIAS otherwise GOOD FDP is the second number GO towards the end of the line is read into an array and the value returned is outputed, in the first line that... (1 Reply)
Discussion started by: cmccabe
1 Replies
IFNDP-PROXY(5)						       Network configuration						    IFNDP-PROXY(5)

NAME
ifndp-proxy[-<interface name>] - IPv6 NDP and IPv4 ARP proxy entries SYNOPSIS
/etc/sysconfig/network/ifndp-proxy /etc/sysconfig/network/ifndp-proxy-<interface name> DESCRIPTION
These files contain IPv6 NDP and IPv4 ARP proxy settings, that should be applied using the ip neigh add proxy command documented in the ip(8) manual page that provides a common interface for IPv4 and IPv6. The NDP/ARP proxy is required, e.g. when IP addresses from the same subnet have to be used on the interface of the host as well as on interfaces behind a (tunnel) interface and using a bridge is not an option. Don't forget to enable forwarding and the NDP/ARP proxy by setting net.ipv6.conf.<all|default|interface name>.proxy_ndp = 1 net.ipv6.conf.<all|default|interface name>.forwarding = 1 and/or net.ipv4.conf.<all|default|interface name>.proxy_arp = 1 net.ipv4.conf.<all|default|interface name>.forwarding = 1 or net.ipv4.ip_forward = 1 either as global all setting in the /etc/sysctl.conf file or using the ifsysctl(5) files, that allow per-interface setup. Forwarding can be also enabled in the /etc/sysconfig/sysctl file using the IP_FORWARD and IPV6_FORWARD variables. The proxy entries are added and deleted using the if-{up|down}.d/ndp-proxy script, every time after an involved interface has been set up or down. SYNTAX
The format of the ifndp-proxy file is: <address> <address interface> <proxy interface list> The format of the ifndp-proxy-<address interface> file is same to above, but allows also to omit the address interface by using a "-" as placeholder inside of the file, because it is already available in the file name: <address> <address interface | -> <proxy interface list> Lines beginning with # and blank lines are ignored. Each line defines to add a proxy NDP/ARP entry with the address of or behind address interface to all interfaces in the proxy interface list. EXAMPLES
Let's assume, your machine is connected via eth0 to a switch with the networks 2001:db8:abba::/64 and 192.168.100.1/24 and is using the IP address 1 itself. You'd like to use the addresses 11 and 12 e.g. for virtual machines behind the tap1 and tap2 interface, that is: 2001:db8:abba::1/64 -- local eth0 address 2001:db8:abba::11/64 -- address behind tap1 2001:db8:abba::12/64 -- address behind tap2 192.168.100.1/24 -- local eth0 address 192.168.100.11/24 -- address behind tap1 192.168.100.12/24 -- address behind tap2 then set up the following entries in the ifndp-proxy file: 2001:db8:abba::1 eth0 tap1 tap2 2001:db8:abba::11 tap1 eth0 tap2 2001:db8:abba::12 tap2 eth0 tap1 192.168.100.1 eth0 tap1 tap2 192.168.100.11 tap1 eth0 tap2 192.168.100.12 tap2 eth0 tap1 additionally to the routing entries in the routes or ifroute-<interface name> files. BUGS
Please report bugs at <https://bugzilla.novell.com/> AUTHOR
Marius Tomaschewski <mt@suse.de> SEE ALSO
ifup(8) ifcfg(5) ifsysctl(8) sysconfig December 2009 IFNDP-PROXY(5)
All times are GMT -4. The time now is 10:09 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy