• Cisco Unified Communications Manager 12 Install Errors on Proxmox/KVM


    The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs. qemu-kvm command: /usr/libexec/qemu-kvm -version QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard ........
  • possible SYN flooding on ctid 42131, port 80. Sending cookies. - Solution


    The Linux Kernel interpretated a very high volume of real traffic as a DDOS attack so it basically ends up blocking your web server. possible SYN flooding on ctid 42131, port 80. Sending cookies. Simple fix edit sysctl values for max_syn_backlog sysctl -w net.ipv4.tcp_max_syn_backlog=5000 To make them permanent edit /etc/sysctl.conf echo "net.ipv4.tcp_........
  • OpenVZ mass ip update


    The file ipupdate.txt should look like this: ip.ip.ip.ip ctid while read -r; do ip=$REPLY setip=`echo $ip|awk '{print $1}'` ctid=`echo $ip|awk '{print $2}'` echo "vzctl set $ctid --ipadd $setip --save" vzctl set $ctid --ipadd $setip --save done < ipupdate.txt........
  • possible SYN flooding on port 80. Sending cookies.


    Errors like this are shown on high usage servers and ports so it is common to see it on http and even imap ports: possible SYN flooding on port 80. Sending cookies. The Linux kernel will even detect flooding on OpenVZ containers: possible SYN flooding on ctid 6000, port 993. Sending cookies. In many cases this is not an issue and is more so simply a result of regular, but high usage traffic.........
  • OpenVZ how to enable FUSE in the container


    vzctl set 2 --devnodes fuse:rw --save Where "2" is the ctid........
  • Openvz Enable netadmin


    vzctl set $CTID --devnodes net/tun:rw --capability net_admin:on --save........
  • Vbox/Virtualbox devices grayed out for non-root user solution


    It is a permissions issue that is hard to fix. All but one USB device is greyed out. I am already a member of "vboxusers" I have already enabled and disabled USB support for the guest. I have already reinstalled the latest VBOx guest editions If running as root it all works fine Changing........
  • OpenVZ Unable to stop container


    vzctl stop ctid Killing container ... Child 1033348 exited with status 7 Unable to stop container vzctl enter ctid enter into CT 29831 failed Some have suggested using vzctl stop ctid --fast which does not work. The only thing that seems to work is restarting the vz service.........
  • OpenVZ backup container to a single file while it's running using "vzdump"


    Proxmox has made this free utility to backup running OpenVZ containers. It's a great program which is actually just a PERL script but gets the job done. This program is not 100% required because all it really does is cp -a from your container's path as far as I know but it is still good to have uniformity to how you backup your containers. For RPM distros such as Centos/RHEL/Fedora etc.. download and install this: wget http://www.proxmox.com/cms_proxm........
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