KEMP Technologies A Company And Product Presentation
Agenda • Introduction • Load Balancing Fundamentals • LoadMaster Base Setup • Core Load Balancing Features • Transparency & Topologies • Loadmaster HA Setup • Advanced Features • Application Specific Aspects • Troubleshooting • Tips & Tricks • Summary
Introducing KEMP • Established in year 2000 • Pioneered “Affordable” Load Balancing & ADC • Global HQ in New York; EMEA HQ Ireland, Sales Germany • US & EMEA based Tech Support, Available 7 X 24 • Specialize in Load Balancing and ADC • Consistent Growth • Technology partnerships with Microsoft, Dell & VMWare • 100% Channel Focused
What is “Server Load Balancing” and Why Do We Need It? Sample Problems / KEMP Solution
Problem # 1 Server and Application Availability
Internet Web/Application Server
Internet X Web/Application Server
Problem # 2 Performance & Scalability
As the number of user requests grows… Wait ! I Can’t Keep UP! Internet Web/Application Server
Problem # 3 Security
Internet Web/Application Server
Wait ! I Can’t Keep UP! Install SSL & IPS On Server Internet Web/Application Server
1 3 5 7 . . . 2 4 6 8 . . . Internet DNS Round Robin Network Infrastructure 10.0.20.5 10.0.20.6 Add another server with DNS Round Robin? Public-Facing IP
2 4 6 8 1 3 5 7 Internet Error 404 Page Not Found DNS Round Robin Network Infrastructure X 10.0.20.6 10.0.20.5 Add another server with DNS Round Robin? Public-Facing IP
Internet 10.0.20.5 Public VIP Server & Application Health Checking Increased Performance & Scalability Improved Management and Administration Private IPs 192.168.0.4 192.168.0.3 192.168.0.2 Server Farm
Internet 10.0.20.5 Public VIP LoadMaster automatically detects server and application failures and dynamically re-routes user requests to other, available servers. X Private IPs 192.168.0.4 192.168.0.3 192.168.0.2 Server Farm
Error 404 Page Not Found Internet X 10.0.20.5 Public VIP X X X Private IPs 192.168.0.4 192.168.0.3 192.168.0.2 Server Farm
Internet 10.0.20.5 Public VIP Active Hot Standby High Availability with Stateful Failover Private IPs 192.168.0.4 192.168.0.3 192.168.0.2 Server Farm
Internet X 10.0.20.5 Public VIP Active Hot Standby High Availability with Stateful Failover Private IPs 192.168.0.4 192.168.0.3 192.168.0.2 Server Farm
Internet X 10.0.20.5 Public VIP Active Out of Service High Availability with Stateful Failover Private IPs 192.168.0.4 192.168.0.3 192.168.0.2 Server Farm
Layer 4 and Layer 7 • Layer 4 Load balancing: • Layer 4 Load Balancing is based on source IP addresses persistence and TCP Connection health checking. • But what about NAT? • What if my server is accepting connections on a port but the service is actually down? • Layer 7 Load balancing: • Layer 7 Load Balancing provides much more capabilities, for example • L7 Based Persistence • Application Healthchecking. • Content Switching
Loadmaster Setup & WUI Overview
Setup & Installation • Connecting to the Loadmaster • Licensing • Network Setup • Update Firmware
Connecting to the Loadmaster • Via Web User Interface • Loadmaster’s default IP address is: 192.168.1.101 • Virtual Loadmaster will use DHCP to get an IP address • Browse to https://192.168.1.101 • Accept the Certificate and you will be prompted for a license code • Connecting via Serial Cable • Use terminal emulation software • Use VT-100 Emulation • 115200bps • 8 data bits • Parity: None • 1 stop bit • Hardware Flow Control
Licensing • License Key Prompt • Note: KEMP EMEA ships all units with a license key applied so this step can be over looked in most cases. • For Virtual Loadmasters you will need to perform this step. Contact KEMP Technologies and quote the Serial Number and Access Code • Access Codes are based on MAC-Addresses so licenses cannot be moved between Virtual Machines.
Network Setup • Once the Loadmaster is licensed, the Quickstart Menu will run and will ask for the following information • ETH0 IP Address • ETH1 IP Address • Hostname • Nameservers • Search Domains • Default Gateway • Reboot the LoadMaster to apply the changes.
Obtaining Loadmaster Firmware • To identify the latest version of firmware on general release visit the news section on our forums. • http://forums.kemptechnologies.com • Contact KEMP support on email@example.com and request a link to download the firmware.
Updating Loadmaster Firmware • Go to System Configuration -> • http://forums.kemptechnologies.com • Contact KEMP support on firstname.lastname@example.org and request a link to download the firmware.
The Web User Interface - WUI • Connect to the WUI via https://IPADDRESSfor all configuration options. • Overview of the WUI.
Scheduling Scheduling & Balancing Methods • Round Robin • Weighted Round Robin • Least Connection • Weighted Least Connection • Fixed weighting • Weighted response time Internet Server 1 Server 2
Server Resource Load Balancing Internet Agent, Adaptive Balancing Methods • CPU Utilization • Memory (RAM) Available • Number of Active Users • Any Perfmon Stat. Next Request CPU=75% CPU=72% Server 1 Server 2
Server Health-checking • Real Server Check Parameters: • ICMP: Verify that the Server is contactable from the Loadmaster • TCP Connection Only: Verify that the Loadmaster can connect to the Real Server on the specified port • HTTP/HTTPS: Waits for a valid response from the Webserver, i.e. 200 OK • Mail (SMTP)/IMAP/POP3: Waits for a valid response from the Mail Server, i.e. 220 SMTP Service Ready
Source IP-based Server Persistence 2 3 1 Internet Issues with Source-IP Persistence ? Shopping Data For User 1 Server 1 Server 2
L7 Server Persistence 2 3 1 • Super HTTP • User Agent + Authorization Header • URL Hash • Same URL = Same Server • Hash of HTTP Query Item • Same HTTP Request Parameter = Same Server Internet Shopping Data For User 1 Server 1 Server 2
Load Balancing Decision Process Server/Application Health Check Internet Persistence Load Balance Server 1 Server 2
Virtual Service Setup • Create a Virtual Service • Set up Health-checking for the Virtual Service • Configure Persistency Options • Configure Scheduling Method. • Add Real Servers
Topologies • In General, configurations can be broken down into 1-arm and 2-arm configurations • Since 1-arm and 2-arm is a distinction on a virtual service basis, Loadmasters can house combinations of 1-armed and 2-armed Virtual Services
1-armed Configuration In 1-armed configurations, the VS and RS are on the same network
2-armed Configuration In 2-armed configurations, the VS and RS are on different networks
Transparency • Transparency is a major factor when planning a Loadmaster Deployment • Transparency – LoadMaster will pass along the original source IP address of the Client. • Non-Transparency– LoadMaster will NAT the address so the source IP address appears to be the LoadMaster • Transparency can be important for logging purposes, but may cause virtual services to respond improperly.
Transparency • All Layer 4 traffic is transparent • Traffic at Layer 7 can be either • Non-Transparency is almost always easier, unless there is a requirement to see the source IP address. • Non-Transparent mode will often fix routing and traffic flow issues
Traffic Restrictions • Two Examples of configurations that will NOT work • 1-armed, Transparent, Clients on same subnet • 2-armed, Transparent, RS’s gateway isn’t the LoadMaster. • Traffic must flow back to the Loadmaster
Direct Server Return • DSR mode is an uncommon configuration • DSR will be covered in our • “Advanced Technical Training Webinar”
High Availability • HA creates a pair of Loadmasters acting as one logical device • Loadmasters must be located on the same subnet in order to be in a HA Pair • Active/Standby • Only one unit is ever handling traffic at a particular moment