SAP Web Dispatcher, Warning, max number of open files

[markus_sap2020]

Hello everybody,

we've installed a new SAP Web Dispatcher 7.77 on RHEL 8.3 Linux for SAP Applications.

The Web Dispatcher is running, but unfortunatly the trace-file (/usr/sap/SAPSID/W00/work/dev_webdisp) shows warnings:

[Thr 140408584731648] *** WARNING => NiIInit: max number of open files per process (1024) < max number of NI handles (31000) [nixxi.cpp 8063]
[Thr 140408584731648] *** WARNING => The maximum number of sockets supported on this host is 1019. This may be insufficient for 15000 connections (icm/max_conn=15000) [icxxman.c 4167]

We 've changed the paramters for Kernel limitations:
[SIDadm@hostname ~]$ ulimit -a
core file size (blocks, -c) unlimited
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 30816
max locked memory (kbytes, -l) unlimited
max memory size (kbytes, -m) unlimited
open files (-n) 128640
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 32768
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
[SIDadm@hostname ~]

Our config without server-connections:
enque/server/max_clients = 4100
icm/cancel_strategy = 2
icm/client_ip_connection_limit = WARN=30, REJECT=50
icm/conn_timeout = 5000
icm/HTTP/admin_0 = PREFIX=/sap/wdisp/admin,DOCROOT=$(DIR_DATA)$(DIR_SEP)icmandir,AUTHFILE=$(icm/authfile)
icm/HTTP/server_cache_0/clear = true
icm/HTTP/server_cache_0/expiration = 28800
icm/HTTP/server_cache_0/http_cache_control = true
icm/HTTP/server_cache_0/max_entries = 50000
icm/HTTP/server_cache_0/max_name_len = 512
icm/HTTP/server_cache_0/max_ufo_entries = 64000
icm/HTTP/server_cache_0/memory_size_MB = 2000
icm/HTTP/server_cache_0 = PREFIX=/, CACHEDIR = $(DIR_DATA)/cache/0
icm/HTTP/server_cache_0/size_MB = 4000
icm/HTTP/server_cache_0/ufo_expiration = 180
icm/keep_alive_timeout = 60
icm/max_conn = 15000
icm/max_threads = 4096
icm/min_spare_threads = 8
icm/min_threads = 128
icm/req_queue_len = 8000
icm/server_port_0 = PROT=HTTP, PORT=8080, TIMEOUT=60, PROCTIMEOUT=900
icm/server_port_1 = PROT=HTTPS, PORT=8443, TIMEOUT=60, PROCTIMEOUT=900
icm/server_port_2 = PROT=HTTPS, PORT=8444, TIMEOUT=60, PROCTIMEOUT=900
icm/server_port_3 = PROT=HTTP, PORT=9080, TIMEOUT=60, PROCTIMEOUT=900
icm/server_port_4 = PROT=HTTPS, PORT=9443, TIMEOUT=60, PROCTIMEOUT=900
icm/server_port_5 = PROT=HTTPS, PORT=9444, TIMEOUT=60, PROCTIMEOUT=900
icm/traffic_control = NETTIMEOUT=5
icm/wp_roll_timeout = 60
is/hostbuffer_timeout_invalid_entry = 2
is/hostbuffer_timeout_valid_entry = 600
is/HTTP/show_detailed_errors = FALSE
is/HTTP/show_server_header = false
mpi/max_pipes = 16000
mpi/total_size_MB = 700
rdisp/http_check = 0
rdisp/plugin_auto_logout = 0
wdisp/HTTP/max_pooled_con = 16350
wdisp/HTTPS/max_pooled_con = 16350
wdisp/HTTP/use_pool_for_new_conn = 1
wdisp/system_conflict_resolution = 1


To solve the problem, we've already taken a look on SAP notes 2007212, 538405 and

https://help.sap.com/doc/saphelp_nw73ehp1/7.31.19/en-US/48/9ab14248c673e8e10000000a42189b/frameset.h...

We've made some changes, but the warnings remain.

Please can you help us?

Kind regards

[markus_sap2020 · Accepted solution]

The solution was to change

DefaultLimitNOFILE in

/etc/systemd/system.conf
cf. https://stackoverflow.com/questions/3734932/max-open-files-for-working-process/38898626

Regards

[cris_hansen]

Hello Markus,

About "*** WARNING => The maximum number of sockets supported on this host is 1019. This may be insufficient for 15000 connections (icm/max_conn=15000) [icxxman.c 4167]", KBA 2107665 says that this is an OS issue.
Maybe you can check this SAP Help page to tune your web dispatcher.

Nevertheless, these are warnings. Have you faced an actual ERROR with this configuration?

Regards,
Cris

[markus_sap2020]

Hello Cristiano,

thanks for your answer.

No, there are no ERRORS with our configuration. But we are confused about this warning, because our limitations of running RHEL 8.3 are high enough.

ulimit -a
core file size (blocks, -c) unlimited
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 30816
max locked memory (kbytes, -l) unlimited
max memory size (kbytes, -m) unlimited
open files (-n) 128640
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 32768
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited

In SAP Note 2107665 is icm/max_sockets mentioned, but in SAP Web Dispatcher 7.77 icm/max_sockets is obsolete.

Regards

[dmcardlenl]

[Is this resolved?]

What does sapwebdisp -checkconfig pf=<ASCS_PROFILE> say?

Re-read https://launchpad.support.sap.com/#/notes/2107665 a few more times.

Delete parameter icm/max_sockets from profiles.