References RightScale Failover
Amazon EC2
Amazon EC2 Information (Instances, Pricing, etc.) http://aws.amazon.com/ec2/ Amazon EC2 Price Calculator http://calculator.s3.amazonaws.com/calc5.html
tcpdump, WireShark/Ethereal
TcpDump Usage of tcpdump: For example monitoring SMTP from a particular host: # tcpdump -w tcpdump.out -s 0 ip host 84.47.53.128 and tcp port 25 WireShark/Ethereal Examine the captured file using tshark: # tshark -r tcpdump.out Executables within wireshark: /usr/sbin/capinfos
Load Balancing for Postfix
There are several possibilities for web or mail server load balancing: Relayd – https://calomel.org/relayd.html Nginx – https://calomel.org/nginx.html The Linux Virtual Server – http://www.linuxvirtualserver.org/ Heartbeat –
OpenVZ Error: No buffer space available
Description In your logs you get an “No buffer space available” error. Analysis Look at your bean counters: # cat /proc/user_beancounters Version: 2.5 uid resource held maxheld barrier limit failcnt 101: kmemsize 9146159 27892508 110559230 113770490 0