Munin looks a lot like rrdtool or MRTG to me. If you like monitoring tools and like writing your own plugins in Perl, may I suggest you look at Argus as well.
With Argus, NetSNMP, and a little Perl I set up monitoring of disk, network, processor, and memory usage on servers; HTTP, outbound SMTP, POP3, IMAP, DNS, RADIUS, L2TP, webmail (including login), main web page (checking for proper page served), sshd (including login), and MX host functionality/response time/uptime; circuit, interface, subinterface, firewall, and tunnel status/uptime/usage; log sizes, backup progress, server room temperature, ticket system accepting logins; and access concentrator stats like ports filled, longest user session, uptime, average connect time per port, average connect time across the concentrator, and even power cycle times and watts drawn through the outlets from the remote-controlled power strips.
It's not that Nagios is bad or anything, or that Argus will necessarily replace either Nagios or Munin for your uses. It's certainly worth a look, I think. I used it to replace a commercial proprietary product my boss at an ISP had been using -- one which we really needed more system licenses when I got there, because he was only monitoring the most essential services to save on software upgrade costs. The proprietary, closed source product also didn't monitor every type of device and service we needed to monitor and required a Windows NT or 2000 license for the server to run it.
I was able to throw Argus and an iptables-based (with some Perl wrapping it) redirector for unpaid subscription accounts on a machine with our L2TP system (with the IP addresses managed by a Perl program). The redirector replaced a $6000 Cisco-branded Windows 2000 machine sold as an appliance, BTW, which had been compromised but for which Cisco wanted a year-long support contract before giving us administrator access. I ran it all on a Pentium 233 pulled from storage, and we never hit a load level over 10, with typical load of 0.5 to 2. My boss called me the Windows killer. I just told him it was Linux, Perl, and a few other neat open-source toys. If only he'd asked more for half-day implementations on Linux before spending money on "solutions"... | [reply] |