AS3 up5 mail問題

eric757

OS是redhat AS3 up5 x86_64版本
在setup裡面有把sendmail設為自動啟動，沒有開啟防火牆

這部主機的IP是10.40.40.30
電腦名稱是top30

/etc/hosts裡面的內容如下
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
10.40.40.30 top30

現在遇到的問題如下
[root@top30 root]# telnet 10.40.40.30 25
Trying 10.40.40.30...
telnet: Unable to connect to remote host: Connection refused
[root@top30 root]# telnet top30 25
Trying 10.40.40.30...
telnet: Unable to connect to remote host: Connection refused

但是當我用localhost或127.0.0.1時卻是可以的
[root@top30 root]# telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
220 top30 ESMTP Sendmail 8.12.11/8.12.11; Thu, 5 Jan 2006 09:23:34 +0800

[root@top30 root]# telnet 127.0.0.1 25
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
220 top30 ESMTP Sendmail 8.12.11/8.12.11; Thu, 5 Jan 2006 09:25:46 +0800


感覺是這部機器不認得自己的ip跟hostname，使得mail系統無法運作\r
請問各位先進這問題該如何解決?