无法启动数据库，报SQL6048N

故障现象：
尝试启动数据库失败：
db2inst1@linux-db2v9:~/sqllib> db2start
03/26/2012 22:57:37     0   0   SQL6048N  A communication error occurred during START or STOP DATABASE MANAGER processing.
03/26/2012 22:58:07     1   0   SQL6048N  A communication error occurred during START or STOP DATABASE MANAGER processing.
03/26/2012 22:58:37     2   0   SQL6048N  A communication error occurred during START or STOP DATABASE MANAGER processing.
03/26/2012 22:59:07     3   0   SQL6048N  A communication error occurred during START or STOP DATABASE MANAGER processing.
SQL1032N  No start database manager command was issued.  SQLSTATE=57019

相关配置：
db2inst1@linux-db2v9:~/sqllib> more db2nodes.cfg
0 linux-db2v9 0
1 linux-db2v9 1
2 linux-db2v9 2
3 linux-db2v9 3

db2inst1@linux-db2v9:~> more .rhosts
linux-db2v9 db2inst1

db2inst1@linux-db2v9:~> more /etc/services   | grep -i db2
ibm-db2         523/tcp    # IBM-DB2
ibm-db2         523/udp    # IBM-DB2
questdb2-lnchr  5677/tcp   # Quest Central DB2 Launchr
questdb2-lnchr  5677/udp   # Quest Central DB2 Launchr
db2c_db2inst1   50001/tcp
DB2_db2inst1    60000/tcp
DB2_db2inst1_1  60001/tcp
DB2_db2inst1_2  60002/tcp
DB2_db2inst1_END        60003/tcp
db2inst1@linux-db2v9:~>

db2inst1@linux-db2v9:~> db2 get dbm cfg | grep -i svc
TCP/IP Service name                          (SVCENAME) = db2c_db2inst1

相关测试：
db2inst1@linux-db2v9:~> ping linux-db2v9
PING linux-db2v9.site (172.20.21.102) 56(84) bytes of data.
64 bytes from linux-db2v9.site (172.20.21.102): icmp_seq=1 ttl=64 time=0.053 ms
64 bytes from linux-db2v9.site (172.20.21.102): icmp_seq=2 ttl=64 time=0.029 ms
--- linux-db2v9.site ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1002ms
rtt min/avg/max/mdev = 0.029/0.041/0.053/0.012 ms
db2inst1@linux-db2v9:~> rsh linux-db2v9
linux-db2v9.site: Connection refused

db2inst1@linux-db2v9:~> db2_all date

linux-db2v9.site: Connection refused

linux-db2v9.site: Connection refused

linux-db2v9.site: Connection refused

linux-db2v9.site: Connection refuse

老觉得rsh这一块配置有问题，但不知道出在哪里。

哪位朋友帮忙看看是怎么回事？

谢谢！