Well, There is no such alternate for cpanel, if you are looking for stable and reliable solution you should go with cPanel without having any second thought. If you are looking for something which is easy and free and stable too then i would suggest you to go with VestaCP. I have been used vestacp couple of times and found very helpfull and relaible.
There are are lot of open source panel available too, however, for a web hoster, it is important that the client gets to do what he needs for his website, so the client panel should be full of features for their ease of managing... CPanel ranks on top for this, then plesk, and then DirectAdmin...
If you are using a RedHat Flavor, you can also check the Centos Web Panel, a good one though, but if you want to sustain in the hosting market, you go to go with the flow, which is what most hosters does and choose cPanel, plesk, or directadmin..
Yeah, directadmin is going to be your best bet, honestly
Tom Whiting, WHMCS Guru extraordinaire
Linux problems? WHMCS Problems? Give me a shout
Check out my WHMCS Addons
+1 - 866-546-8914 / skype - admin_139201 / twitter/facebook - @whmcsguru
cPanel is certainly what I recommend, but you could look at Virtualmin.
__________________ Hostirian - Saint Louis Data Center and Dedicated Servers Provider - (800) 615-9349
Colocation, Cloud Servers & Managed WordPress Solutions
Nearly 20 years of IT experience | SSAE-18 Certified, HIPAA Compliant Insanely Fast PCIe NVMe Servers
When I started my company I wrote my own in Perl CGI. It took me about 40 hours to write a script that would handle client orders. I knew nothing about software that I could buy. Even though I had used Plesk awhile back when I hosted my sites before having my own server, I hadn't thought about that. So I had this amazing script (It wasn't half bad and worked flawlessly) but I wasn't getting customers. So even though I felt good about the program I produced, visitors to my site saw it differently because they weren't buying hosting plans. And I have some pretty good plans.
I've used both Plesk and cPanel and have tried the DirectAdmin demo. They are all good. After getting rid of the one I wrote, the first one I used was Plesk because I had learned that well. Later I learned about cPanel and was frustrated a bit having to learn new software. So I added a server with cPanel and suddenly began getting orders. I found it is the most popular and once I learned it myself liked it better than Plesk even though Plesk is still a top choice.
I learned that in this business it's important to make it as easy for the client and give them the most you can. In my experience, cPanel does that best.
__________________ Chosen Web Host Quality Shared web hosting and Design
Integrity with Excellence - Free backups through cPanel
You can't develop the internet, until you learn to develop yourself