I have used MySQL Enterprise Monitor for a year and a half, and although some believe its a superior product, its 5K per server per year for the Enterprise version. I just started using MONyog a month ago, and purchased it today.
I bought the Unlimited Pack and that is a perpetual license for an unlimited amount of servers. It gives me all the monitoring I need and without an agent installed on the MySQL server. That makes the sys-admins I work with very happy.
My prefered feature is the log analyzer. It makes analysing the slow-query-log and the general-log really easy and efficient.
Cool product, check it out if you can.
Christos Kalantzis - Hightail (Previously called YouSendIt.com)
Soon after downloading MONyog I had setup 63 DB servers for 27 clients in about 2 hours. Today, I have dealt with a client that has 2 DB Servers, 1 MySQL Instance on DB1 and 3 MySQL Instances set up as read slaves all converted to all MyISAM. I was able to monitor when the client restarted apache and dropped hundreds of DB Connections that the client’s app was not releasing. I was able to see spikes in DB Connection requests. I ran the Query Analyzer on the PROCESSLIST that accurately showed nice query profiles. I was able to rule out certain MySQL gotchas in favor of suspecting the client’s app of spawning new DB Connections and not properly closing web pages. All of this while on the phone with the Client. I called over my Company's owner, and two of my supervisor’s and another Linux engineer and had them look at the graphs I was using to monitor the client. They like the product very much.
I’ve only had this product 6 days and have tripled/quadrupled my productivity today. This is a truly a "MySQL DBA out the box" software solution.
Rolando Edwards - LogicWorks
Monyog is reasonable, it was easy to setup and it is very useful for effective monitoring. Monyog cuts through the noise and helps us identify the key MySQL performance metrics that bear an impact on our database performance. It’s important for my team to be on top of MySQL database performance. Monyog seamlessly helps them in their roles by gathering past as well as real-time insights for greater effectiveness.
We needed a way to gather, store, and analyze historical query data in order to identify slow queries and deadlocks across 1700 customer sites that were spread across 70 database servers. We also were looking for an easy to understand UI to give access and insight to our customer support staff and operations teams none of whom are formally trained as DBA’s.
MONyog has literally taken the guess work out of managing our
MySQL replicated cluster! Thank you Webyog!
Matt McAlister - MSoft eSolutions Ltd
MONyog is the best out-of-the-box GUI monitoring tool for MySQL that
I have seen. It "just works." As promised, getting up and running
quickly is easy, and having a centralized location for monitoring is
very useful. The graphs are beautiful and the statistics that are
graphed are useful time-savers.
The biggest difference between MySQL's Enterprise Monitor and MONyog
is that MONyog is agentless. At Pythian, we have many clients with
differing security requirements. Requiring a daemon process to be
running is not something we currently do, and it might be a hard sell
for some clients. Even if every client was amenable to it, making sure
the daemon is up and running on each MySQL server is tedious. Note
that agentless operation works for every feature, including log
analysis as well as operating system statistics.
Sheeri Cabral - The Pythian Group
MONyog is actually both interactive and noninteractive, so you might want to examine its capabilities for both kinds of monitoring.
High Performance MySQL, 2nd Edition - O'Reilly
Monitoring downtime and performance tuning is paramount for a product that enables end users to run their own copy of tickets and their database thereby eliminating bad user experience.