System Management options
This table shows the available options on the System Management tab:
Option | Description |
---|---|
Minimum Available Disk
Space Minimum Free Memory |
For Minimum Available Disk Space, the engine processes and monitor daemon automatically shuts down when the file system on which the Cloverleaf root is installed has less free disk space then the configured parameter. For Minimum Free Memory, the engine processes and monitor daemon automatically shut down when the amount of memory available to the system is less than the configured parameter. For version 19.1 and above, the application checks physical memory only. For versions 6.2 and below, the application checks all memory (physical + virtual/swap). |
This enables the Port From and Port To fields. The
port range must have at least four ports. For example, specifying a
range of 10000-10003 allocates ports 10000, 10001, 10002, and 10003. Valid Port From ports are 1025-65532. Valid Port To ports are 1028-65535. The formula for determining the port range is: Minimum port number = (total number of processes)X2 + (total number of protocol threads) + 1. |
Ephemeral best practice
Optimizing ephemeral port usage can reduce Support calls and improve performance.
Ephemeral ports are used to have finer grain control over the
connection. The main use of configuring ephemeral ports is for TCP interfaces to access several ports other than a TCP protocol thread.Ephemeral port optimization includes consideration of these points:
- When all sites use the same range, for example, 29300-42100,
hcimonitord issues can result. For
example:
[cmd cmd :ERR /0:_hcimonitord_:08/08/2019 08:55:36] Invalid command length (>= 8192). Closing connection 0xb9e38b50. [aler:aler:INFO /0:_hcimonitord_:08/08/2019 08:55:36] Removing alerts and waits for connection 0xb9e38b50 [icl tcpi:DBUG /0:_hcimonitord_:08/08/2019 08:55:36] Tcpip shutting down socket 1600
Best Practice: Remove explicit ephemeral ranges or select each site to use its own range of 500-1000 ports, based on site size.
- Ephemeral ports give you fine grain control over the Server-Client
relationship. By configuring these ports, you TCP interfaces have access to
several ports other than a TCP protocol thread.
Best Practice: Do not use TCP ports in Cloverleafs' protocols that are in the operating system’s ephemeral range.
- The port range is implementation dependent. Factors to consider
include the number of TCP interfaces, multi-threaded TCP/IP interfaces, ICL
communications, protocol threads, hcimonitord
connections, and number of processes.
Best Practice: Configure a beginning and ending port range.
- Each operating system uses a unique port range. For example, a range of
32768-61000 forces Cloverleaf to use that range and not use the operating
system's defined range. This range is large enough for a given Cloverleaf
site.
Although multiple Cloverleaf sites can use the same range, this is not recommended as it circumvents the design and usage of the Cloverleaf ephemeral range. Each site must have its own range that does not interfere or coincide with other Server ports on the Server.
Best Practice: Employ a large range of ports.
- Using a narrower range of a 500-1000 should reserve enough
connections for a given Cloverleaf site; however, each site must be tailored by
its usage.
Best Practice: Do not have any TCP servers in any Cloverleaf site that are in this range, since an ephemeral port could be using the port.
- To decide which port numbers to use, you must ensure a wide
enough range is used to accommodate all of the traffic for the site’s
interfaces.
Best Practice: Use a range that is not a reserved range for other applications or interfaces, and where there are no Cloverleaf interfaces configured to listen.
- A Cloverleaf site’s ephemeral port range is customizable. For customization,
you can configure the port range to not use the operating system’s predefined
range.
Best Practice: Configure the port range to not use the operating system's ephemeral range. This is typically in the range of 32768 to 60999. For example, on RHEL you can use
cat /proc/sys/net/ipv4/ ip_local_port_range
. - You must determine how large to make the range. For example, a small range
of 40000-40004 could cause issues. The range depends on the site's
configuration.
Best Practice: The system requires at a minimum: (Total Number of Processes X 2) + (Total Number of Protocol Threads + 1).
- When Implementation determines that an ephemeral port range must be set and
the range specified opened in a firewall, or other reasons, then the Implementer
decides the range size to use.
Firewalls do not typically restrict outbound traffic, or internal traffic to the operating system traffic.
Best Practice: The system requires at a minimum: (Total Number of Processes X 2) + (Total Number of Protocol Threads + 1).