PQ78320: ONE OF THE SERVER THREADS IS "STUCK" IN THE R-STATEIN THE SERVER-STATUS DISPLAY.

APAR status
Closed as program error.

Error description
Customer description:
When we install the WAS 5.0 it seems to work ok, but when
 you monitor the "server-status" of the IHS, you can see that
 we are "loosing" sessions.
The sessions get stuck in READ (R) state, and eventually we
 expect we will run out of sessions (we have a max of
300/server).
 In the attached "ServerStat.txt" you can see some sessions in
theR-state.
After running for 5 hours yesterday we had arround 120 sessions
in the R-state.

Development's description:
 The client is opening a socket on the SSL port for IHS, the
server then
 begins the SSL Handshake process by initiating a read() to
receive the
 'client hello' message which should be the first message sent
by the
 client. However, the client never sends any data and never
closes the
socket. As a result, IHS is hung in the read() indefinitely.
This is
 caused by the fact that in order to complete the handshake, the
socket
 must be in blocking mode. The Gskit developers are reviewing
the doc to
 confirm this, after which we will look at how this should be
resolved.
Local fix Problem summary
If a client opens a connection to the SSL
socket but never sends any data, it will cause the IHS/Apache
child handling the request to hang. The child status on the
server-status output will show a 'R'. The problem exists for
IHS 1.3.x on Windows and 2.0.42 on all platforms.
Problem conclusion
The problem is caused by IHS waiting to
receive the SSL Client Hello handshake message while using
blocking mode on the socket with no time-out set. The client
never sends the 'Client Hello' message causing IHS to wait
indefinitely. The problem is resolved by using the setsockopt()
function to set a send/receive timeout value on Windows and to
use non-blocking I/O with a select on the 2.0.42 Unix versions.
The following COMPID's are affected by these changes:
5648B7800 IHS for AIX
5648B7801 IHS for Sun
5648B7802 IHS for WinNT and Win2K
5648B7803 IHS for HP
5648B7804 IHS for Linux

The fix will be available in the next service refreshes for IHS,
currently planned as IHS 1.3.26.2 and IHS 2.0.42.2.
The code changes are stored in CMVC under defect 
PQ74214.
Temporary fix Comments
APAR information
APAR number PQ78320
Reported component name WAS HTTP SERVER
Reported component ID 5630A3603
Reported release 00W
Status CLOSED PER
PE NoPE
HIPER NoHIPER
Special Attention NoSpecatt
Submitted date 2003-09-10
Closed date 2003-09-10
Last modified date 2003-09-10

APAR is sysrouted FROM one or more of the following:
PQ74214

APAR is sysrouted TO one or more of the following:

Modules/Macros
IBMSSL          

Publications Referenced

Fix information
Fixed component name WAS HTTP SERVER
Fixed component ID 5630A3603

Applicable component levels
R00W PSN    UP


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > IBM HTTP Server > Runtime
Operating system(s):
Software version: 00W
Software edition:
Reference #: PQ78320
IBM Group: Software Group
Modified date: Sep 10, 2003