Shell Programming and Scripting

awk  -v RS=    '/\[2153\]|\[4324\]|\[9999\]/ { a=NR }  NR==a, NR==a+1'  ORS="\n\n"   filename  >  output

$ cat d.sh
#! /bin/sh

if [ $# -ne 2 ]; then
        echo "Usage: $0 <input> <pattern>"
        exit 1
fi


awk '
BEGIN {
        RS=""
        FS="\n"
}
NR%2==1 && $1 ~ /\['$2'\]/ {
        getline
        print
}' $1

$ cat d.in
[2153]

ASRVSERV=1241GD;
BPCONN=avtr213;
OMGEO=FIET

[4324]

ASRVSERV=333TS;
BPCONN=AUTO1243;
OMGEO=TSAM

[4858]

ASRVSERV=345RE;
BPCONN=ABC123;
OMGEO=MSAM

[8888]

ASRVSERV=899AS;
BPCONN=CAR1234;
OMGEO=IAOS

[8912]

ASRVSERV=728WW;
BPCONN=POP1239;
OMGEO=JKAE

[1211]

ASRVSERV=999UI;
BPCONN=LOC1932;
OMGEO=UISE

$ ./d.sh d.in 4324
ASRVSERV=333TS;
BPCONN=AUTO1243;
OMGEO=TSAM

$ ./d.sh d.in 8912
ASRVSERV=728WW;
BPCONN=POP1239;
OMGEO=JKAE

$ ./d.sh d.in 1111

$