How to match for an empty string in a grep pattern search?
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0
I have a set of files containing boot variables from several cisco switches in the network. I have an requirement to filter only the switches with the boot variable empty on the next reload and print the hostname
given this data
hostname1#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable =
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
hostname2#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable = flash:cat9k_iosxe.bin;
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
desired result
hostname1
BOOT variable =
Thanks!
awk sed grep file-search
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
add a comment |
0
I have a set of files containing boot variables from several cisco switches in the network. I have an requirement to filter only the switches with the boot variable empty on the next reload and print the hostname
given this data
hostname1#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable =
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
hostname2#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable = flash:cat9k_iosxe.bin;
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
desired result
hostname1
BOOT variable =
Thanks!
awk sed grep file-search
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
Thanks for the answers .. still trying to get them work... Couple of catches..1. we cant play around with the keyword 'hostname' they are just examples.. they may be just random, meaning one can have jax-sw-1 and another can have lhr-sw-1 ... 2. There is a space after the equal sign in Boot variable = .. i am sorry if this changes anything in the answer.. will accept the answer(or the closest one) once i figure out.. if you have more inputs please share in here! Thanks
– Maran Ganesh
Jan 16 at 20:46
add a comment |
0
0
0
I have a set of files containing boot variables from several cisco switches in the network. I have an requirement to filter only the switches with the boot variable empty on the next reload and print the hostname
given this data
hostname1#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable =
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
hostname2#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable = flash:cat9k_iosxe.bin;
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
desired result
hostname1
BOOT variable =
Thanks!
awk sed grep file-search
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
I have a set of files containing boot variables from several cisco switches in the network. I have an requirement to filter only the switches with the boot variable empty on the next reload and print the hostname
given this data
hostname1#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable =
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
hostname2#show boot
---------------------------
Switch 1
---------------------------
Current Boot Variables:
BOOT variable = flash:cat9k_iosxe.bin;
Boot Variables on next reload:
BOOT variable = flash:cat9k_iosxe.bin;
Manual Boot = no
Enable Break = no
Boot Mode = DEVICE
iPXE Timeout = 0
desired result
hostname1
BOOT variable =
Thanks!
awk sed grep file-search
awk sed grep file-search
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
asked Jan 16 at 2:42
Maran GaneshMaran Ganesh
244
244
Thanks for the answers .. still trying to get them work... Couple of catches..1. we cant play around with the keyword 'hostname' they are just examples.. they may be just random, meaning one can have jax-sw-1 and another can have lhr-sw-1 ... 2. There is a space after the equal sign in Boot variable = .. i am sorry if this changes anything in the answer.. will accept the answer(or the closest one) once i figure out.. if you have more inputs please share in here! Thanks
– Maran Ganesh
Jan 16 at 20:46
add a comment |
Thanks for the answers .. still trying to get them work... Couple of catches..1. we cant play around with the keyword 'hostname' they are just examples.. they may be just random, meaning one can have jax-sw-1 and another can have lhr-sw-1 ... 2. There is a space after the equal sign in Boot variable = .. i am sorry if this changes anything in the answer.. will accept the answer(or the closest one) once i figure out.. if you have more inputs please share in here! Thanks
– Maran Ganesh
Jan 16 at 20:46
Thanks for the answers .. still trying to get them work... Couple of catches..1. we cant play around with the keyword 'hostname' they are just examples.. they may be just random, meaning one can have jax-sw-1 and another can have lhr-sw-1 ... 2. There is a space after the equal sign in Boot variable = .. i am sorry if this changes anything in the answer.. will accept the answer(or the closest one) once i figure out.. if you have more inputs please share in here! Thanks
– Maran Ganesh
Jan 16 at 20:46
Thanks for the answers .. still trying to get them work... Couple of catches..1. we cant play around with the keyword 'hostname' they are just examples.. they may be just random, meaning one can have jax-sw-1 and another can have lhr-sw-1 ... 2. There is a space after the equal sign in Boot variable = .. i am sorry if this changes anything in the answer.. will accept the answer(or the closest one) once i figure out.. if you have more inputs please share in here! Thanks
– Maran Ganesh
Jan 16 at 20:46
add a comment |
3 Answers
3
active
oldest
votes
1
awk 'a[++i]=$0/BOOT variable =.$/for(x=NR-10;x<=NR;x++)print a[x]' filename|awk '/^hostname/||/BOOT variable =.$/print $0'| sed "s/#.*//g"
Results in:
hostname1
BOOT variable =
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
add a comment |
4
You could do something like
awk -F'#' '
$2 == "show boot" hostname = $1
/BOOT variable =[ t]*$/ print hostname; print
' file
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
orawk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print'-- requires gawk I think for the complex FS.
– glenn jackman
Jan 16 at 16:43
add a comment |
0
Using grep and pipes:
grep -B8 -E '= $' file |grep -E 'hostname|= $'
The first grep extracts the line where there's nothing after '=' symbol and 8 lines before the match to extract the line with hostname.
The second grep filters the lines with hostname and BOOT variable =
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
1
awk 'a[++i]=$0/BOOT variable =.$/for(x=NR-10;x<=NR;x++)print a[x]' filename|awk '/^hostname/||/BOOT variable =.$/print $0'| sed "s/#.*//g"
Results in:
hostname1
BOOT variable =
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
add a comment |
1
awk 'a[++i]=$0/BOOT variable =.$/for(x=NR-10;x<=NR;x++)print a[x]' filename|awk '/^hostname/||/BOOT variable =.$/print $0'| sed "s/#.*//g"
Results in:
hostname1
BOOT variable =
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
add a comment |
1
1
1
awk 'a[++i]=$0/BOOT variable =.$/for(x=NR-10;x<=NR;x++)print a[x]' filename|awk '/^hostname/||/BOOT variable =.$/print $0'| sed "s/#.*//g"
Results in:
hostname1
BOOT variable =
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
awk 'a[++i]=$0/BOOT variable =.$/for(x=NR-10;x<=NR;x++)print a[x]' filename|awk '/^hostname/||/BOOT variable =.$/print $0'| sed "s/#.*//g"
Results in:
hostname1
BOOT variable =
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
edited Jan 16 at 16:51
Jeff Schaller
40.8k1056129
40.8k1056129
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
answered Jan 16 at 16:33
Praveen Kumar BSPraveen Kumar BS
1,424138
1,424138
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
add a comment |
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
``` awk 'a[++i]=$0/BOOT variable = .$/for(x=NR-10;x<=NR;x++)print a[x]' results_* |awk '/#/||/BOOT variable = .$/print $0'| sed "s/#.*//g" ``` with some slight edits i was able to get this work.. thanks!
– Maran Ganesh
Jan 16 at 21:24
add a comment |
4
You could do something like
awk -F'#' '
$2 == "show boot" hostname = $1
/BOOT variable =[ t]*$/ print hostname; print
' file
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
orawk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print'-- requires gawk I think for the complex FS.
– glenn jackman
Jan 16 at 16:43
add a comment |
4
You could do something like
awk -F'#' '
$2 == "show boot" hostname = $1
/BOOT variable =[ t]*$/ print hostname; print
' file
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
orawk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print'-- requires gawk I think for the complex FS.
– glenn jackman
Jan 16 at 16:43
add a comment |
4
4
4
You could do something like
awk -F'#' '
$2 == "show boot" hostname = $1
/BOOT variable =[ t]*$/ print hostname; print
' file
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
You could do something like
awk -F'#' '
$2 == "show boot" hostname = $1
/BOOT variable =[ t]*$/ print hostname; print
' file
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
answered Jan 16 at 2:54
steeldriversteeldriver
35.9k35286
35.9k35286
orawk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print'-- requires gawk I think for the complex FS.
– glenn jackman
Jan 16 at 16:43
add a comment |
orawk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print'-- requires gawk I think for the complex FS.
– glenn jackman
Jan 16 at 16:43
or
awk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print' -- requires gawk I think for the complex FS.– glenn jackman
Jan 16 at 16:43
or
awk -F '#| *= *' '$2 == "show boot" host = $1 NF > 1 && $2 == "" print host; print' -- requires gawk I think for the complex FS.– glenn jackman
Jan 16 at 16:43
add a comment |
0
Using grep and pipes:
grep -B8 -E '= $' file |grep -E 'hostname|= $'
The first grep extracts the line where there's nothing after '=' symbol and 8 lines before the match to extract the line with hostname.
The second grep filters the lines with hostname and BOOT variable =
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
add a comment |
0
Using grep and pipes:
grep -B8 -E '= $' file |grep -E 'hostname|= $'
The first grep extracts the line where there's nothing after '=' symbol and 8 lines before the match to extract the line with hostname.
The second grep filters the lines with hostname and BOOT variable =
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
add a comment |
0
0
0
Using grep and pipes:
grep -B8 -E '= $' file |grep -E 'hostname|= $'
The first grep extracts the line where there's nothing after '=' symbol and 8 lines before the match to extract the line with hostname.
The second grep filters the lines with hostname and BOOT variable =
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
Using grep and pipes:
grep -B8 -E '= $' file |grep -E 'hostname|= $'
The first grep extracts the line where there's nothing after '=' symbol and 8 lines before the match to extract the line with hostname.
The second grep filters the lines with hostname and BOOT variable =
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
edited Jan 17 at 15:32
Jeff Schaller
40.8k1056129
40.8k1056129
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
answered Jan 16 at 3:23
Emilio GalarragaEmilio Galarraga
51929
51929
add a comment |
add a comment |
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Thanks for the answers .. still trying to get them work... Couple of catches..1. we cant play around with the keyword 'hostname' they are just examples.. they may be just random, meaning one can have jax-sw-1 and another can have lhr-sw-1 ... 2. There is a space after the equal sign in Boot variable = .. i am sorry if this changes anything in the answer.. will accept the answer(or the closest one) once i figure out.. if you have more inputs please share in here! Thanks
– Maran Ganesh
Jan 16 at 20:46