TCP/IP EST connection

[Jasmine Gardner]

How long will a HP-UX server stay in an EST state without receiving any new data?

[Stefan Farrelly]

/usr/bin/ndd -get /dev/tcp tcp_keepalive_interval

Shows the time period. For more info;

ndd -h tcp_keepalive_interval

To change it see man ndd but this is only temporary - you need to change it in /etc/rc.config.d/nddconf to make it permanent when you reboot.

[rick jones]

From the standpoint of TCP:

If the connection is not sending any data at the same time, it will stay in ESTABLISHED until the remote sends either a FIN or a RST segment. If the remote have dropped off the face of the network, that could be quite a long time...

If the connection has enabled keepalives via setsockopt(SO_KEEPALIVE), then after tcp_keepalive_interval milliseconds of idleness the connection will start sending keepalive probes. If no response to the keepalive probes is received within tcp_ip_abort_interval, the connection will be aborted. If replies are received, the connection will remain in ESTABLISHED.

ftp://ftp.cup.hp.com/dist/networking/briefs/annotated_ndd.txt