A controller-determined limit exists to the number of Transmission Control Protocol/Internet Protocol (TCP/IP) connections that can be made to the controller before it stops responding to subsequent connection attempts. The type of management operations being performed and the number of management sessions taking place together determine the number of TCP/IP connections made to a controller. This problem is self-correcting because, after some TCP/IP connections terminate, the controller then becomes responsive to other connection attempts.
Does anyone knows what does limits are?
I found that the latest version of SMonitor (11.40.0A00.0003) can have many connections to the same management IP in ESTABLISHED state, and that eventually I loose connectivity to the management IP. Looks like I'm hitting the limit the documentation refers to, but I'm curious if those values are known, and even if they can be tweaked.
For all controllers except the E2800 and E5700, the management connection limit is 32. If 32 active management connections are reached, no more connections will be allowed until the connection count drops to 24. For E2800 and E5700 controllers, there are two types of management connections, REST/HTTPS and SYMbol/RPC. For these controllers the active connection limit is 15 for REST/HTTPS and 16 for SYMbol/RPC. The limits are per controller and are not user configurable.
That said, the SMmonitor in version 11.40.0A00.0003 of SANtricity Storage Manager has an issue where it may not properly close connections to the controllers when running on Linux. This would result in the behavior you have described. A fix is planned for early 2018. A workaround is available in the meantime to correct the issue. To perform the workaround, modify the SMMONITOR_JVM_OPTS parameter in /var/opt/SM/smclient.properties to match the following: