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1 reply Latest Post - ‏2011-03-09T08:38:27Z by SystemAdmin
SystemAdmin
SystemAdmin
134 Posts
ACCEPTED ANSWER

Pinned topic Netstat showing many ports in CLOSED state

‏2011-02-24T02:42:10Z |
Hi experts,

I see thousands of ports in following state (by running netstat -Aan):-
<---
PCB/ADDR Proto Recv-Q Send-Q Local Address Foreign Address (state)
f1000e001014f3b0 tcp4 0 0 . . CLOSED
f1000e00102c8bb0 tcp4 0 0 . . CLOSED
f1000e000fe47bb0 tcp4 0 0 . . CLOSED
-->

This eventually caused my java applications to throw "Too many open files" error and none of the application can open any ports (for DB/networking etc). When I check the PCB add, I noticed most of the ports owned by a Java process, but not sure how it's creating so many ports (probably connection leak?)

However, can anyone explain what does "CLOSED" state actually means. In normal cases, I never seen CLOSE in any netstat results. Also, local or foreign address usually associate with an address but in this case it's showing '*.*'. Any pointers will be helpful.

This issue is happening in AIX 6.1

Regards,

Sara
Updated on 2011-03-09T08:38:27Z at 2011-03-09T08:38:27Z by SystemAdmin
  • SystemAdmin
    SystemAdmin
    134 Posts
    ACCEPTED ANSWER

    Re: Netstat showing many ports in CLOSED state

    ‏2011-03-09T08:38:27Z  in response to SystemAdmin
    In addition to above, I noticed the following behavior too. I created a simple Java application that will create socket (port 8990) and close it after sometime. Following is the 'lsof' taken when the application is running. Noticed that two other ports UDP 59924 and TCP 53106 was created as well which was not accessed/created in my application at all. This issue is only observed in one of our AIX and not seen in other environment. Any reason for this behavior?

    Value of I :157 np:0
    COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
    java 5636600 webmetho cwd VDIR 10,8 0 0 /bmc/local (/dev/hd1)
    java 5636600 webmetho 0u VCHR 26,0 0t6805 0 / (/dev/hd4) (like character special /dev/pts/0)
    java 5636600 webmetho 1u VCHR 26,0 0t6805 0 / (/dev/hd4) (like character special /dev/pts/0)
    java 5636600 webmetho 2u VCHR 26,0 0t6805 0 / (/dev/hd4) (like character special /dev/pts/0)
    java 5636600 webmetho 3r VREG 10,5 0 0 /usr (/dev/hd2)
    java 5636600 webmetho 22u IPv4 0xf1000e000af7fc00 0t0 UDP *:59924
    java 5636600 webmetho 37u IPv6 0xf1000e000b0dd3b0 0t0 TCP *:8990 (LISTEN)
    java 5636600 webmetho 38u IPv6 0xf1000e000b9502a0 0t0 TCP localhost:*->localhost:53106