linux - using sed / awk to change variable values in config files -


this question has answer here:

i have few config files , wanting edit variable values using script. i've come across sed/awk this. have tried using following sed command on following config example, issue changes commented section actual one. did see can nth occurrence seams apply line, not entire file.

command:

sudo sed -i 's/server=.*/server=10.10.1.206/' /etc/zabbix/zabbix_agentd.conf

file

### option: server #       list of comma delimited ip addresses (or hostnames) of zabbix servers. #       incoming connections accepted hosts listed here. #       if ipv6 support enabled '127.0.0.1', '::127.0.0.1', '::ffff:127.0.0.1' treated equally. # # mandatory: no # default: # server=10.10.1.206  server=10.10.1.206

add regex anchor ^ replace on lines starting server

sudo sed -i 's/^server=.*/server=10.10.1.206/' /etc/zabbix/zabbix_agentd.conf

the support anchors ^ , $ match start , end of pattern available in posix compatible sed versions.

an excerpt regular-expressions page,

anchors

[..] anchors not match characters. match position. ^ matches @ start of string, , $ matches @ end of string.[..]


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