VPS not booting - Sentora fresh install

[bRte]

I am using ChicagoVPS.
Today, i did a fresh install of Centos 6.6, later, installed Sentora.

It was working fine, for couple of hours, but then,
my VPS went offline.

Staff from VPS provider told me that,  it has to do with conntrack sessions,
so he white listed my single IP.
So, i was thinking, if only one IP was dropped, ok, i could access from another location.
Then i found out that, conntrack sessions could cause high memory usage,
and VPS provider can, automatically suspend that account.

Still waiting from support to reply on my ticket,
so i was thinking to ask here for any guidance.

VPS is 50gb hdd, 2gb mem

And, this is response from them:

Wed, 01 Apr 2015 11:03:41 -0400 VPS 25242 (192.227.141.163) has 181272 conntrack sessions

Wed, 01 Apr 2015 11:03:42 -0400 SUSPENDING VPS 25242 (192.227.141.163); it has 181272 conntrack sessions
Wed, 01 Apr 2015 11:03:42 -0400 Possible DoS VPS 25242 (192.227.141.163): 199074 pps during 5 second interval (whitelisted)

As i suspected.
VPS was having too much sessions, and i was suspended.
Limit is 5500 per VPS, and it breached somehow with this panel.
Cpanel was working previously, w/o any problems.

[Active8]

Did you made any custom changes after he fresh install ?
I have dozens of Sentora installs even on a 512 MB VPS and never had this kind of problem

Use this command to see all of the sessions: cat /proc/net/nf_conntrack
Once you see the sessions, you can determine what IPs are connecting and over what port, then use the port to discover the protocol.

It could be an DDoS attack to your ip

[bRte]

No custom changes prior the install.
Problem occurred upon Sentora install.
But i solve it with limiting conntrack to 5500, as support suggested.
The bad thing is, it happened 2-3 hrs when i was offline.

DDoS could be, but only 3 sites where pointing to my IP from CloudFlare.
Now i fixed it, and build pretty good iptables rules.

It came to my mind that, maybe it has to do with the installation.
I mean, cpanel didn't had any problems, maybe simply because they might have conntrack limit included in install script, dunno...

[wormsunited]

That is strange i never had those problems before... sentora works great with me on my dedicated servers and on my vps too. I have 2 vsps running on sentora one with 100GB and 2GB and other with 150 GB with 4GB all run great without any issues. Could that be also a problem with your hosting provider limits too? dont know....