Linux server prerequisites

Hardware prerequisites

Make sure you've checked the Hardware prerequisites before you start configuring your server.

Mandatory prerequisites

Here is the list of the mandatory prerequisites; if they're not met, the node will refuse to start:

  • at least 2 CPU cores on the server
  • a 64-bits operating system
  • an Oracle Java 8 64-bits JVM — provided by the node itself but can be changed
  • at least as much physical memory than the memory configured for the JVMthe JVM cannot use more memory than available RAM
  • for user limits on the operating system:
    • at least 65536 user processes
    • at least 65536 opened files
    • unlimited usage of physical and virtual memory

System prerequisites

A node currently supports the following software prerequisites:

  • 64-bit Linux Operating System:
    • Red Hat Enterprise Linux: 5.x6.x, 7.x

      For Red Hat EL 7, avoid kernel 3.10.0-123.el7 as there is a bug that is seriously affecting Axway Decision Insight.

      Kernel panics can happen (see 1127947 on bugzilla.redhat.com).

      Install a later kernel version or patch this version with patch level >= 3.10.0-123.20.1.el7.

    • Ubuntu: 14 LTS, 16 LTS

      For Ubuntu 14 LTS, avoid kernels 3.13 to 3.15.4 as there is a bug in the Linux kernel shipped with some versions of Ubuntu (see https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1323165).

      You may want to upgrade the operating system to fix it. 

    • SUSE: 11, 12
    • Oracle Linux: 6.x, 7.x
    • Amazon Linux distribution
    • Microsoft Azure Linux distribution

Configuration prerequisites

Please check the following configurations have been properly applied to your environment:

Accounts

Account Required abilities
<Decision Insight administration account>
  • Permissions

    Directory Permissions
    <install directory> read, write, execute

    <working directory>

    read, write, execute

    <logging directory>

    read, write, execute
<Decision Insight execution account>
  • Permissions

    Directory Permissions
    <install directory> read, execute
    <working directory> read, write, execute
    <logging directory> read, write, execute
<System administration account>
  • Register a service
  • Update system configuration files such as /etc/security/limits.conf

<install directory> is the directory where the node will be installed.

<working directory> is the directory where the node will write its data (by default, <working directory> is <install directory>/var).

<logging directory> is the directory where the node logs will be stored (by default, <logging directory> is <working directory>/log).

NTP

Server clock must be synchronized with an NTP server.

When running in a virtual environment, is it recommended to configure NTP at the hypervisor level and to install "tools" in the virtual machine in order that it has a "stable" clock.

System-wide resources limits tuning

On all Linux operating systems, you must ensure that system-wide resources limits are adequate. More specifically, check the following parameters:

Name Name in configuration file limits.conf Description Required value
max number of open file descriptors nofile Maximum number of files (sockets included) a process can open >= 65536
max user processes nproc Maximum number of processes (threads included) a single user can have >= 65536
max memory size rss Maximum amount of memory a process can take unlimited
virtual memory as Maximum amount of virtual memory a process can take unlimited

You can see the current configuration with ulimit -a:

core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 513157
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 63336
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
cpu time               (seconds, -t) unlimited
max user processes              (-u) 65536
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

To change these parameters, edit the /etc/security/limits.conf  configuration file by adding the following lines:

  • For Red Hat Enterprise Linux

    /etc/security/limits.conf
    <Decision Insight execution account> soft nproc 65536
    <Decision Insight execution account> hard nproc 65536
    <Decision Insight execution account> soft nofile 65536
    <Decision Insight execution account> hard nofile 65536
  • For Ubuntu or Amazon Linux distribution

    /etc/security/limits.conf
    <Decision Insight execution account> soft nofile 65536
    <Decision Insight execution account> hard nofile 65536
  • For SUSE

    /etc/security/limits.conf
    <Decision Insight execution account> soft nproc 65536
    <Decision Insight execution account> hard nproc 65536
    <Decision Insight execution account> soft nofile 65536
    <Decision Insight execution account> hard nofile 65536
    <Decision Insight execution account> soft rss unlimited
    <Decision Insight execution account> hard rss unlimited
    <Decision Insight execution account> soft as unlimited
    <Decision Insight execution account> hard as unlimited

For more information on how to change these parameters temporarily or permanently, see:


The node logs the effective limits during the startup so you can verify that the settings are correctly applied. If the values are not correct, the node will not start and you must update your OS configuration in order to fulfill the requirements

2016-11-23 17:40:13,829 [FelixStartLevel] INFO platform - Reading process OS limits from /proc/16707/limits
2016-11-23 17:40:13,829 [FelixStartLevel] INFO platform - --------------------------------------------------------------------------------
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Limit                     Soft Limit           Hard Limit           Units
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max cpu time              unlimited            unlimited            seconds
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max file size             unlimited            unlimited            bytes
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max data size             unlimited            unlimited            bytes
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max stack size            8388608              unlimited            bytes
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max core file size        0                    unlimited            bytes
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max resident set          unlimited            unlimited            bytes
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max processes             524288               1048576              processes
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max open files            1048576              1048576              files
2016-11-23 17:40:13,834 [FelixStartLevel] INFO platform - Max locked memory         65536                65536                bytes
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max address space         unlimited            unlimited            bytes
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max file locks            unlimited            unlimited            locks
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max pending signals       257439               257439               signals
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max msgqueue size         819200               819200               bytes
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max nice priority         0                    0
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max realtime priority     0                    0
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - Max realtime timeout      unlimited            unlimited            us
2016-11-23 17:40:13,835 [FelixStartLevel] INFO platform - --------------------------------------------------------------------------------

Related Links