I have a dedicated server running CentOS which has been been running fine for a while now.
On the odd day Apache used to hang, I presume due to load so I installed SIM (System Integrity Manager) to check the status of httpd and to re-start when necessary.
Every now and again SIM would email saying that apache was re-started, no big deal.
Then this morning I got a email from SIM saying apache was down but couldn't be re-started. I then logged into the shell and tried to do a: service httpd restart
I then got a message saying something like: could not bind to port 80. I then tried to kill all httpd processes and re-start apache but the problem persisted. I then just rebooted my server and apache started fine.
Since then I have had hundreds of emails from SIM saying that it has had to re-start apache. Somehow it is detecting it as down and re-starting it. Apache seems to be up and fine. Re-installing SIM does not help.
The weird thing is when I logged in using Putty I got the "server's host key did not match the signature supplied" message like something had changed.
Rkhunter does not return anything just a couple of warnings.
Does anybody know what would cause sim to constantly detect Apache as down in this situation and also how this could happen with no changes being made?
For the last week, my vps (directadmin on centos on xen) has become unresponsive every three days at approximately 5 AM, and I'm baffled about why. It doesn't crash, but it stops accepting incoming connections until it's rebooted.
I'm not sure how to troubleshoot this. /var/log/messages gives no useful information. There are no unusual cronjobs running at that time.
Anyone heard of anything like this before or have any advice about how to troubleshoot?
We had a Coldfusion site running MySQL without issues. We are in the process of doing some upgrades and as part of that we recently switched over to MSSQL 5. Ever since that happened, we will have random page hangs. This usually happens on pages with more complex queries, but it is very random. There is no timeout error on the server, no page cannot be displayed errors, no errors of any kind, the page will just hang. We have been monitoring our server resource monitor and we can see when the page 'gives up', we will go from 100% CPU down to almost 0, and then the page simply never recovers. Does anyone have any idea what might be going on? When there is no error message of sorts it makes it very problematic to troubleshoot.
I installed latest kernel ( 126.96.36.199 or 188.8.131.52 ) with grsec which either panics or hang on reboot before reaching boot prompt, just when /sbin/init runs. Experienced the same with grsec patched kernel 184.108.40.206 on several servers with the same hardware.
On server with AMD Operton, I was able to successfully compile 220.127.116.11 with grsec and boot into.
Server hardware details --------------------------
[root@server kernels]# cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU 5148 @ 2.33GHz stepping : 6 cpu MHz : 2333.469 cache size : 4096 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr dca lahf_lm bogomips : 4670.51
processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU 5148 @ 2.33GHz stepping : 6 cpu MHz : 2333.469 cache size : 4096 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr dca lahf_lm bogomips : 4667.16
[root@server ~]# uname -a Linux server.name 18.104.22.168-grsec #1 SMP Tue Jan 15 07:08:50 CST 2008 i686 i686 i386 GNU/Linux [root@server ~]#
[root@server ~]# cat /etc/modprobe.conf alias scsi_hostadapter usb-storage alias eth0 e1000 alias eth1 e1000 alias scsi_hostadapter1 aacraid alias scsi_hostadapter2 ata_piix alias scsi_hostadapter3 usb-storage alias usb-controller ehci-hcd alias usb-controller1 uhci-hcd [root@server ~]#
I am using apache proxypass to proxy to 4 different ports (java/jsp applications) with the following configurations (for each):
<VirtualHost *:80> ProxyPreserveHost On ProxyRequests Off ServerName *****.org ProxyPass / http://*****.org:8080/ retry=0 ProxyPassReverse / http://*****.org:8080/ </VirtualHost>
Everything seems work fine until an awkward delay / connection timeout occurs. The web application hangs for about 5 to 15 seconds and starts working normally after that period. It's certainly not the application's issue because everything is fine when using IP address to access it.
When I enabled the debug log in apache, I found out that every time the server seems to hang, the following error appears in the apache error log and the number of apache child processes keep on increasing (ps aux | grep apache).
[Thu Apr 11 10:20:41 2013] [debug] proxy_util.c(1818): proxy: grabbed scoreboard slot 4 in child 13208 for worker proxy:reverse [Thu Apr 11 10:20:41 2013] [debug] proxy_util.c(1837): proxy: worker proxy:reverse already initialized [Thu Apr 11 10:20:41 2013] [debug] proxy_util.c(1934): proxy: initialized single connection worker 4 in child 13208 for (*) [Thu Apr 11 10:20:41 2013] [debug] proxy_util.c(1818): proxy: grabbed scoreboard slot 3 in child 13208 for worker http://*****.org:8080/ ..... Also, the access log (access.log) completely stops during that hang period.
This debug message keeps on repeating as long as Apache/web-application is not responding. The application starts to work normally after that duration and the number of apache child process decrease to the normal number.
Apache version : 2.2.16 (Debian) OS : Debian GNU/Linux 6.0 root@server:~# apache2 -V Server version: Apache/2.2.16 (Debian) Server built: Nov 30 2012 08:58:36
We are looking for a VPS to house a scala framework running on a JVM, from what I can gleen Xen would be the best route for us or is it possible that openVZ with enough dedicated ram would suffice, does anyone have a view on this?
Just how it actually works? I have a pretty good knowledge about Xen and Linux KVM (somewhat about VMware as well). Prior to joining WHT, I rarely heard about Virtuozzo and OpenVZ.
I'm just interested in RAM usage actually. I also read on some threads that you can oversell storage and net bandwidth as well? That just seems a little weird to me. I also used a fairly good amount of Solaris Zones as well.
Example, if I have a 8GB box and I leave some, say 512MB, reserved for CT0. 8192-512=7680 (I know the ACTUAL RAM amount will NOT be 8192), that leaves 7680MB use for CTs. So technically in OpenVZ if you dice out dedicated 512MB VEs... you end up with 15 right?
So you are able to sell more than 15 VPSs on a 8GB server box? If also set all burstable RAM to 1GB for all VEs.
In Xen, when you set dedicated RAM it is taken away from dom0, period. That's all there is to it, no oversell (Xen 3.3+ you can use ballooning to overcommit RAM, I know). Within CT in VZ, user is able to check beancounters to see the guaranteed/burstable RAM. Technically you can't lie to the users.
I researched around... when oversell in VZ and the RAM gets maxed out... VZ will try to slow/stop/kill processes in order to keep the guests happy, to me that's just dangerous. Why needs to kill processes for RAM saturation?
Anyone can shed some lights for me? Or point me to an article(s). It can be technical, I should be able to grasp.
I am trying to create some vps using openvz but after creating the vps with the Centos basic template 304mb i can't ping the ip and i can't view the centos welcome page in my browser (using ip and not domain, so i don't need to change there anything yet) and the most important is that i can't connect to the vps using ssh
I aks for many good users about my problem but i don' found a solution yet.
I ask my DC about ip's and they told me that the ip's are routed in my server.
When you're creating VPS container, you can ssh with that IP and login with your username and password correct? But, what is the problem when I successfully created a VPS, and when trying ssh into it, I can't. Ok, here we go. I want to create a 2nd vps and will be using it as my DNS server. I enter a set of IPs into HyperVM's IPpool. First IP: x.x.x.178 Last IP: x.x.x.182 Resolv Entries (space Separated) : Gateway (IP): x.x.x.x.177 NetMask: 255.255.255.248
Then I created a vps resource plan. And then I created a VPS and it use the first IP from above. I want to connect to SSH and want to make it as my DNS server but seems the IP are not responding, it wasn't even live. So, what is the problem here? Where I did wrong? Just to let you know, I successfully created 1 VPS before that and it works without any hiccups. Got even whm/cpanel installed as well on it. The thing that I suspected is that my DC pulled the IPs off me and assigned them to other server. Waiting for their reply on this though.
recently I got a VPS from cheapvps.co.uk and so far so good. Im getting used to the VPS enviroment. I tried to follow several guides about how to secure with noexec and nosuid the /tmp and /var/tmp and it did not work.
in http : / / www . webhostingtalk .com/showthread.php?t=474681&highlight=tmp points it must be done from the hosting. Same is said in http : // kb . swsoft . com/article_130_648_en.html.
I asked the hosting to do it and they told me as I got an Unmanaged VPS they cant do it for me.
Do anyone know how can be done ? I dont want to use tmpfs as it uses main memory.
i am looking to get away from hostgators extremely overloaded servers and get a vps. I have been admining linux servers for a while although never as a web server, but think i can handle that aspect. I have done a huge amount of research but dont know which way to go. One of the things thats rough is the control panels, i like cpanel and have only used cpanel but many charge alot for it. I have been considering an xl-256 plan from vpsland.com. they are east coast (i am in NJ, west coast is out) and their xl plan is xen with swap. But its $15 for cpanel and that is too much, i was thinking of trying directadmin for $6. Is directadmin any good? I need spamassasin and that stuff of course. To me its crazy that openvz has no swap and the server will crash if you reach max ram like at vpslink.com. I really liked vpslink.com's phone support but the west coast thing is rough. I have been looking at http://www.ubiquityservers.com/vps/new-york.php these guys but its virtuozzo, but cpanel is cheap only $5 a month. bodhost.com seemed cheap at $8 for cpanel. then i found this which sounds great! especially since its close but i emailed them to ask if its xen or openvz and havent heard back in almost 12 hours which scares me for support. i like phone support but vpslink.com again was on the west coast. their cpanel was cheap though at $8. plus i dont know if i want managed ro not then i remembered this site, and remembered i had gotten alot of help hear before so i figured it be best to hear others experience and favorites, etc.