[HP-UX] Established ports although LAN is disconnected.


 
Thread Tools Search this Thread
Operating Systems HP-UX [HP-UX] Established ports although LAN is disconnected.
# 1  
Old 09-28-2009
[HP-UX] Established ports although LAN is disconnected.

Hi,

I have a few questions.

There is a CORBA connection between 2 HP-UX 11.11i hosts.
Then the LAN of the 2nd host is pulled.

On the 1st host all connections disappear, as expected.
But on the 2nd host all connections still are present, as established.
With lsof one can see that the CORBA processes are still connected to those ports.

My questions are about the port management.

Isn't this a HP-UX core issue ?
Aren't there checks that ensure that a port only can show established, if the other side shows the same ?
Can it be that an application keeps ports established, whilst on interface level this is not possible ?

It appears to be possible, but I would assume it to be the other way around.
I would assume that netstat would show no connection or perhaps time_wait.
That the application thinks the connection is still established, is the problem of the application.
I would expect that on interface level I get the valid port information.

Greetings,

E.J.
# 2  
Old 09-29-2009
Ive seen SUNs and AIXs acting the same way... So I doubt it being an HP-UX core issue, I always understood "whoever (application) opens a connection is responsible for closing it" but you do point out the fact "what about network partial failure?". I have no answer just like you but hope someone can enlighten us...
# 3  
Old 09-30-2009
Quote:
vbe;So I doubt it being an HP-UX core issue, I always understood "whoever (application) opens a connection is responsible for closing it"
Thanks for replying.
It is always difficult to use the right technical terms and phrases, so my question may have come across a bit unclear.

First of all, I think it could be a general TCP/IP question, not really related to HP-UX.
It is just that it happens between 2 HP-UX boxes.

What I meant to say about it being a HP-UX core issue is that I expected the netstat information to come from the HP OS (for example the LAN adapter or so) and not from the applications that use ports/sockets.
Probably it is better to talk in TCP/IP terms, but one should know how Smilie

The assumption "whoever (application) opens a connection is responsible for closing it" makes sense, but in case of my issue, it forces me to take
into account that the netstat information is "unreliable".
Or better said: I have to keep in mind that this output is based on the information provided by the applications. A mind-shift.

In my case the LAN cable is pulled, so the first layer in the TCP/IP model, the link layer, is not present any more.
One box did the expected and released all related ports/sockets.
The other box is still pretending all is well.
As long as the application keeps the sockets in the established state, netstat will report them as established.
Which makes sense actually, while writing this, in principle the applications (application processes) are the best source for this, as they rely on this.

Anyway, bit by bit it is getting clearer, although I do not understand why the 2nd box is keeping the connections established.
I will read some TCP/IP information now, always useful Smilie

E.J.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Red Hat

Nohup with ampersand & process gets disconnected

For years I have spawned shell scripts with nohup and ampersand and they run whether or not I stay logged in. Recently a client told us that we had to set a keep alive timeout on all of our Redhat 7.6 Linux servers. Our sysadmin set the following parameters in the sshd_config file on all of our... (10 Replies)
Discussion started by: gandolf989
10 Replies

2. UNIX for Beginners Questions & Answers

Ssh gets disconnected after idle.

My SSH to server got frozen after idle for a couple of hours. My related configuration are: In my /etc/ssh/sshd_config: ------------------------------------------ ClientAliveInterval 30 ClientAliveCountMax 4 TCPKeepAlive yes ------------------------------------------ and my ~/.ssh/config:... (6 Replies)
Discussion started by: yifangt
6 Replies

3. Solaris

Gnome shows defaultfixed as disconnected

Hello, I have enabled defaultfixed and added the net0 per the solaris 11 documentation. I'm able to ping outside like google and internally but I'm just not sure why the gnome network utility shows wired(net0) as disconnected. Any ideas? Thank you ---------- Post updated 04-08-15 at 08:47 AM... (0 Replies)
Discussion started by: solaris128
0 Replies

4. Red Hat

Ftp gettting disconnected

All, Trying to ftp to a remote ftp server. See following output: ftp -dv xx.xx.xx.xx Connected to xx.xx.xx.xx (xx.xx.xx.xx). 220 Microsoft FTP Service Name (xx.xx.xx.xx:username): ftpuser ---> USER ftpuser 331 Password required for ftpuser. Password: ---> PASS XXXX 230 User logged... (1 Reply)
Discussion started by: Tommyk
1 Replies

5. IP Networking

ESTABLISHED web process??

I put lsof -i -P -n into the terminal and this is the output. I believe i am being hacked?? lsof -i -P -n COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME SystemUIS 1578 melodysneed 9u IPv4 0x07d608ec 0t0 UDP *:* SystemUIS 1578 melodysneed 11u IPv4 0x0ba68810... (5 Replies)
Discussion started by: melodysneed
5 Replies

6. IP Networking

Local Lan, no-ip directed DNS forward, surf within lan

Hi, We have a website running on a local centos 5.4 surfer, static IP. The domain.com uses no-ip.com to take care of the DNS, it forwards all to my server. My router receives the port 80 call, routes it to my server and the world can see domain.com perfectly fine. However, we cannot see... (3 Replies)
Discussion started by: lawstudent
3 Replies

7. Solaris

How to reconnect to a disconnected remote ssh session

hi all How to reconnect to a disconnected remote ssh session on solaris 10 is there any way (4 Replies)
Discussion started by: h@foorsa.biz
4 Replies

8. Solaris

How to configure private LAN and coporate LAN on the same machine-Solaris10

Hi , I am trying to configure a private LAN and corporate LAN on the same machien on Solaris 10. How can I achieve this? Thanks (1 Reply)
Discussion started by: deedee
1 Replies

9. Solaris

Monitor displays Cable disconnected

Hi all This is my first post in this forums. I hope some one can help me with this my Sun Ultra 60 worked fine couple of months back when i used a dell (1280x1024). i move to a MN last month n bought a new sony monitor with (1280x1024) but when i connect it to the box it monitor displays... (1 Reply)
Discussion started by: venuavula
1 Replies

10. IP Networking

Sniffing an established port

Hi All, On a solaris box A port B in which port B is established and receiving data. My question is how do i listen on that established port , how can i get the data received at box A: port B through my application I had searched the forum for the same, but i am unable to retrieve the... (5 Replies)
Discussion started by: matrixmadhan
5 Replies
Login or Register to Ask a Question