Cisco Local Director™
An Implementation Perspective
Presented by Louis Rael
Louis.Rael@gtedc.gte.com
GTE Directories Corp.
GTE Directories Corporation
12/01/97
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Opening Remark
“You have to be professional in approach,
design, and implementation regardless of
your business constraints”
GTE Directories Corporation
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 Goal
“Fulfillment of HTTP requests with multiple servers
using one IP address and one URL” - Jan., 1996
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Round Robin DNS Approach
 The ability to access multiple servers with one Domain Name e.g.
Cisco.com
 T. Kwan, R. E. McGarth, D. A. Reed “NCSA’s World Wide Web
Server: Design and Performance” Computer 1995, pp. 68-74
 E. D Katz, Eric Dean, M McGarth, “Scalable HTTP Server: The
NCSA Prototype” Computer Networks and ISDN Systems, Vol. 27,
1994, pp. 155-164
 Bind 4.9.2 by Godsil, Joseph M. National Center for Supercomputing
Applications Networking Development Team
 bind.492.ncsa.patch
 Implemented on a HP-UX 9.x OS
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 DNS Production Environment
Round Robin DNS
Remote user
10Mb Ethernet
Sun Server 1000
100Mb
FDDI
T3
URL’s serviced
superpages1.gte.net
10Mb Ethernet
T3
superpages2.gte.net
superpages3.gte.net
yp1.gte.net
yp2.gte.net
24X7 Operation
GTE Directories Corporation
yp3.gte.net
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Issues of DNS Implementation
 Reinitialize Domain Name Server (DNS)
 45 minutes to 2 hours from time of removal of
WKS from DNS
 Other ISP’s cached the “A Rec’s” for faster
response i.e. AOL, CompuServe, ...
 Set TTL to 15 minutes
 Lacked responsiveness to business and
development needs
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Potential Solution
Networkers - Network the World
Dallas Convention Center May 7-9, 1996
Distributed Director: Scalable Network
Services by Traina, Paul
Product release date July, 1996
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Local Director Features
 45-MBPS throughput
 combined total of 8000 virtual IP addresses and real
servers
 200Mhz Pentium Pro Processor
 32 MB RAM
 two 10 Mb Ethernet adapters, optional 100 Mb Ethernet
 Optional hot stand-by fail over mechanism
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Test Methodology
Simulate production environment
Logical Topology Map
Physical Topology Map
Map out Local Director configuration
Test Local Director through put
Test the load balance feature
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Test Environment
Web Browsers
Performix/CS Driver
HP J200
DNS Server
Windows
95
Cisco 4000
Hub
Windows
3.11
HP PC Win NT 4.0
Cisco 4000
SGI Indy Irix 6.2
Local Director
Web Servers
Hub
Sun Sparc Server 1000E
10 Mb Ethernet
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Test LD Throughput
Simultaneously request different HTML
pages to eliminate server caching
Client simulation 1, 5, 10, 15, 20,26,24
10 BaseT shared Hub connection
Performix/CS capture playback tool
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Lessons Learned
 Do the physical & logical map first
 Use a “Clean Room” approach to testing
 Start from the bottom up in network problem
solving using the OSI model
 Three days for set-up and testing is tight
 “If you can afford it, wait until the product
matures to avoid being the rev. 1.0 pioneer”
GTE Directories Corporation
12/01/97
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Local Director Configuration
: Local Director Version 1.5.5
syslog output 20.7
no syslog console
hostname ld_yp
interface ethernet 0 100basetx
interface ethernet 1 100basetx
mtu 0 1500
mtu 1 1500
no ping-allow 0
no ping-allow 1
ip address 207.117.125.229
255.255.255.240
route 0.0.0.0 0.0.0.0 207.117.125.238 1
route 0.0.0.0 0.0.0.0 207.117.125.238 1
no rip passive
no failover
telnet 206.251.124.4 255.255.255.0
telnet 207.117.125.254 255.255.255.255
telnet 192.168.1.1 0.0.0.0
no snmp-server contact
no snmp-server location
virtual 207.117.125.227 is
real 207.117.125.226 is
real 207.117.125.225 is
real 207.117.125.232 is
real 207.117.125.233 is
real 207.117.125.235 is
real 207.117.125.236 is
GTE Directories Corporation
weight 207.117.125.226 8
weight 207.117.125.225 8
weight 207.117.125.232 13
weight 207.117.125.233 13
weight 207.117.125.235 13
weight 207.117.125.236 13
timeout 207.117.125.226 15
timeout 207.117.125.225 15
timeout 207.117.125.232 15
timeout 207.117.125.233 15
timeout 207.117.125.235 15
timeout 207.117.125.236 15
bind 207.117.125.227 207.117.125.236
bind 207.117.125.227 207.117.125.235
bind 207.117.125.227 207.117.125.233
bind 207.117.125.227 207.117.125.232
bind 207.117.125.227 207.117.125.225
bind 207.117.125.227 207.117.125.226
threshold 207.117.125.226 30
threshold 207.117.125.225 30
threshold 207.117.125.232 30
threshold 207.117.125.233 30
threshold 207.117.125.235 30
threshold 207.117.125.236 30
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Dissected Configuration
[no] syslog {host|console} ip
no syslog console
do not log data to the system console
syslog output facility.level
syslog output 20.7
Logs messages to the syslog server i.e. a UNIX server
using UDP connection from the output LOCAL4(20) in debug mode (7)
hostname newname
hostname ld_yp
Name of the given local director name
interface ethernet unit {10baseT|100BaseTX|100full|auto}
interface fddi unit
interface ethernet 0 100basetx
interface ethernet 1 100basetx
configures the interface cards to the respective speeds
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Dissected Config. Continued
mtu unit vol
mtu 0 1500
mtu 1 1500
sets the maximum transmission unit (MTU) value for the specified interface (unit)
The default interface for ethernet is 1550
ip address ip [subnet_mask]
ip address 207.117.125.229 255.255.255.240
Assigns an IP address to the local Director
[no] route dest_net net_mask gateway [metric]
route 0.0.0.0 0.0.0.0 207.117.125.238 1
route 0.0.0.0 0.0.0.0 207.117.125.238 1
Adds a static route to the IP routing table. Specified with the default dest_net and net_mask specified with all zeros
(0.0.0.0). The next value is the optional distance metric defaulted to the value of 1
no rip passive
disable RIP routing table updates.
Note: use the ip route command if no rip is being used.
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Dissected Config. Continued
no failover[active]
no failover
Enable access to the optional fail over feature configures
[no] telnet ip mask
telnet 206.251.124.4 255.255.255.0
telnet 207.117.125.254 255.255.255.255
telnet 192.168.1.1 0.0.0.0
Adds authorized IP addresses and corresponding mask for Telnet access to Local Director
(note: up to 16 telnet sessions are allowed)
snmp-server contact text
snmp-server location text
snmp-server host ip_address
no snmp-server contact
no snmp-server location
indicates no system administrator name or contact is supplied with the MIB II compliant SNMP agent. No facility location is
supplied as well
(Note: recommend that SNMP be supplied to operation personnel for proper notification)
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Dissected Config. Continued
[no] virtual virtual_id [virtual_port] [service-state]
virtual 207.117.125.227 is
Creates a virtual server to connect to the network. The service state is in service (is)
Note: when using the command show virtual will show the state as being in-service (is), out-of-service(oos)
[no] real real_id [real_port] [service-state]
real 207.117.125.226 is
Define a real server with the given IP address and the server satate, either in-service (is) or out-of-services (oos)
[no] weight real_id number
weight 207.117.125.226 8
weight 207.117.125.232 13
Defines the weighting factor given to each of the real servers, e.g. 8 has a smaller weight then 13 therefore the
125.226 server will receive less requests then the 125.232 server.
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Dissected Config. Continued
timeout real_id minutes
timeout 207.117.125.226 15
Set the connection timeout for real_id machine. Connection types for example: Telnet sessions that are connected and idle for
the default 15 minutes duration will be logged out
Note: Every two minutes, Local Director will remove connections that have not been fully established through TCP
handshaking
[no] bind virtual_id real_id [real_id ...]
bind 207.117.125.227 207.117.125.236
Associates a virtual server with one or more real servers.
threshold real_id connect_failures
threshold 207.117.125.226 30
Sets the value of the real_id to the number of connect_failures before the real_id is taken out of service.
Note: after a number of minutes (set by the retry command) have passed the server is placed into TEST mode. If during the
testing state a connection is established then Local Director will place the real_id to IS (in-service).
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12/01/97
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New Topology
HTTP Server with Database back-end
Small queries large results
yp1 ... ypn
OC-3
Hub
OC-12
sp1 ... spn
Local Director
cg1 ... cgn
Local Director
Static HTTP Servers
small queries small results
100 BaseT
GTE Directories Corporation
Hub
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Interoperability
2 - SGI Challenge L series
1 - SGI Challenge DM
2 - SGI Challenge S series
2 - Bay Network 100 BaseT hubs
2 - Cisco Local Director
4 - Origin 200
4 - Origin 2000
1 - Data Vault
1 - SGI O2
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Closing Remark
“You have to be professional in approach,
design, and implementation regardless of
your business constraints.”
GTE Directories Corporation
12/01/97
21
Team Approach
Team Members Biggs, Bob
Broadon, LC
Donohoo, Malcolm
Rael, Louis
Ruten, Stephen
Ward, Matt
Witzel, Ronnie
GTE Directories Corporation
Bob.Biggs@gtedc.gte.com
LC.Broaden@gte.net
Malcolm.Donohoo@gtedc.gte.com
Louis.Rael@gtedc.gte.com
Stephen.Ruten@gtedc.gte.com
Matthew.Ward@gte.net
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Questions & Answers
?
?
?
Pizza! Hold the Anchovies!!!
GTE Directories Corporation
12/01/97
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