Taken from db2 Infocenter these step let you configure first db2 instance on linux.
1) Create Users for db2:
groupadd -g 999 db2iadm1
groupadd -g 998 db2fadm1
groupadd -g 997 dasadm1
2) Create users for each group:
useradd -u 1004 -g db2iadm1 -m -d /home/db2inst1 db2inst1
useradd -u 1003 -g db2fadm1 -m -d /home/db2fenc1 db2fenc1
useradd -u 1002 -g dasadm1 -m -d /home/dasusr1 dasusr1
3) Set initial password:
passwd db2inst1
passwd db2fenc1
passwd dasusr1
4) Create Instance:
/opt/ibm/db2/V9.7/instance/dascrt -u dasusr1
/opt/IBM/db2/V9.7/instance/db2icrt -a server -u db2fenc1 db2inst1
/opt/ibm/db2/V9.7/cfg/db2ln
5) Setup Comunication:
cp /etc/services /root/services.BCK
echo db2c_db2inst1 50001/tcp >> /etc/services
su – db2inst1
db2 update database manager configuration using svcename db2inst1
db2set DB2COMM=tcpip
6) Restart DB:
db2stop
db2start