Extracting a part of String using grep/sed

Question

I have a file in linux with similar entries as below

dn: CN=HP_NetworkSupport,OU=groups,DC=HDFCSLDM,DC=COM
dn: CN=Review users,OU=groups,DC=HDFCSLDM,DC=COM
<         


        

Answer 1

Using sed:

$ sed -r 's/.*CN=([^,]*),.*/\1/' inputfile
HP_NetworkSupport
Review users