July 24, 2014

SAP disp+work stop. DNS issue for servers with multiple SID

For reference in case you have DNS server issue with SAP servers having multiple named instance. This is good learning when working with multiple named SAP host.
The parameter below bypasses the need of SAP to reference DNS server and identify itself as the named host name.

Error/Symptoms:
1 No change performed.
2 Very slow SAP processing due to semi dialog standstill.
3 Multiple SAP instances go into dialog standstill.
4 All SAP process ends after 30 minutes.
5 DIA work process stay in Run status and end of dev_w0 log is below
6 dev_w0 log involves gateway routing to localhost and not named instance
Gateway issues detected when doing a trace on work process.
M Tue Jul  1 03:30:04 2014
M  *** ERROR => GwConnectSapWp: GwConnect to
localhost / sapgw17 failed (rc=NIECONN_PENDING) [gwxx.c       1842]
M  ***LOG S0T=> GwConnectSapWp, GwConnect (-0012) [gwxx.c       1848]


7 After 30 minutes the session is ended.
Workaround:
rdisp/reverse_name_lookup=0     disable reverse name lookup of user-terminals 
gw/resolve_phys_addr=0          disable reverse name lookup for gwrd

Permanent Solution:
DNS flush. Find named instance conflict or stuck entries in DNS server.

Please take note that this is a workaround. We still need to correct DNS conflict within the SAP network.