How to Keep Alive SSH Sessions

Many NAT firewalls time out idle sessions after a certain period of time to keep their trunks clean. Sometimes the interval between session drops is 24 hours, but on many commodity firewalls, connections are killed after as little as 300 seconds. To avoid having your SSH sessions become unresponsive after e.g. 5 minutes, do the following:
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Postfix limit

Postfix a way to limit the frequency of brute force?
In file /usr/local/etc/postfix/main.cf place something like the following:

Code:
...
# RATE THROTTLING
smtpd_client_connection_rate_limit = 20
smtpd_error_sleep_time = 10s
smtpd_soft_error_limit = 3
smtpd_hard_error_limit = 5
...

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Diplaying Logs with journalctl [CentOS7]

To simply view the logs on your system, you can execute the following command:

journalctl

This will display the logs with the oldest entries first. Although this is simple, it is not very useful since we do not tend to read logs like a book.

By default journalctl displays the logs in a pager. It shows you one page of logs requiring you to hit the space bar to proceed.

Diplaying Logs by Date (more…)

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How to Upgrade Payara Server

The answer to the question of “how do I upgrade?” is always “it depends”, because everyone’s situation is going to be slightly different. This blog will cover some of the most straightforward ways which should apply in the majority of cases.

Either of the following two methods would work in most circumstances:
Backing up and restoring the existing configuration to a new installation
Maintaining completely separate domain and node directories and pointing the new version to the existing directories (more…)

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