Config nginx with Boost?

Follow this node: http://groups.drupal.org/node/26363
I use this sitting with my nginx with boost but when start nginx ,it said :
I use this sitting but when start nginx ,it said:
duplicate location "/" in

## 6.x starts
location / {
#rewrite ^/(.*)/$ /$1 permanent; # remove trailing slashes - disabled
try_files $uri @cache;
}

How can i soldve this ?
And how to convert any .htaccess to nginx config?I want to know the basic rule for this?
Thanks!

#######################################################
### nginx.conf BEGIN
#######################################################
#
pid /var/run/nginx.pid;
user www www;
worker_processes 4;
worker_rlimit_nofile 8192;

events {
worker_connections 4096;
use epoll;
}

http {
## MIME types
include /etc/nginx/fastcgi.conf;
include /etc/nginx/mime.types;
default_type application/octet-stream;

## Size Limits
client_body_buffer_size 1k;
client_header_buffer_size 1k;
client_max_body_size 10m;
large_client_header_buffers 3 3k;
connection_pool_size 256;
request_pool_size 4k;
server_names_hash_bucket_size 128;

## Timeouts
client_body_timeout 60;
client_header_timeout 60;
keepalive_timeout 75 20;
send_timeout 60;

## General Options
ignore_invalid_headers on;
limit_zone gulag $binary_remote_addr 1m;
recursive_error_pages on;
sendfile on;
set_real_ip_from 0.0.0.0/32;
real_ip_header X-Forwarded-For;

## TCP options
tcp_nodelay on;
tcp_nopush on;

## Compression
gzip on;
gzip_buffers 16 8k;
gzip_comp_level 9;
gzip_http_version 1.1;
gzip_min_length 10;
gzip_types text/plain text/css image/png image/gif image/jpeg application/x-javascript text/xml application/xml application/xml+rss text/javascript image/x-icon;
gzip_vary on;
gzip_static on;
gzip_proxied any;
gzip_disable "MSIE [1-6]\.";

## Log Format
log_format main '"$http_x_forwarded_for" $host [$time_local] '
'"$request" $status $body_bytes_sent '
'$request_length $bytes_sent "$http_referer" '
'"$http_user_agent" $request_time "$gzip_ratio"';

client_body_temp_path /var/cache/nginx/client_body_temp 1 2;
access_log /var/log/nginx/access.log main;
error_log /var/log/nginx/error.log crit;

#######################################################
### nginx.conf catch-all
#######################################################

server {
limit_conn gulag 10;
listen 127.0.0.1:88;
server_name _;
root /data/u/$host/;
index index.php index.html;

## Deny some crawlers
if ($http_user_agent ~* (HTTrack|HTMLParser|libwww) ) {
return 444;
}
## Deny certain Referers (case insensitive)
if ($http_referer ~* (poker|sex|girl) ) {
return 444;
}
## www. redirect
if ($host ~* ^(www\.)(.+)) {
set $rawdomain $2;
rewrite ^/(.*)$ http://$rawdomain/$1 permanent;
}

##
## required only when using purl, spaces & og for modules: ajax_comments, watcher and fasttoggle
## the /og path should be modified to match your default for og/purl URL for organic groups
##
location ~* ^/og {
rewrite ^/og\-(.*)/ajax_comments/(.*)$ /index.php?q=ajax_comments/$2 last;
rewrite ^/og\-(.*)/context/ajax-block-view$ /index.php?q=context/ajax-block-view last;
rewrite ^/og\-(.*)/comment/reply/(.*)\?reload=1$ /index.php?q=comment/reply/$2&reload=1 last;
rewrite ^/og\-(.*)/node/([0-9]+)/toggle/(.*)$ /index.php?q=node/$2/toggle/$3 last;
rewrite ^/og\-(.*)/node/([0-9]+)/edit\?(.*)$ /index.php?q=node/$2/edit?$3 last;
rewrite ^/og\-(.*)/user/([0-9]+)/watcher/toggle/(.*)$ /index.php?q=user/$2/watcher/toggle/$3 last;
rewrite ^/(.*)$ /index.php?q=$1 last;
}

## 6.x starts
location / {
#rewrite ^/(.*)/$ /$1 permanent; # remove trailing slashes - disabled
try_files $uri @cache;
}

location @cache {
if ( $request_method !~ ^(GET|HEAD)$ ) {
return 405;
}
if ($http_cookie ~ "DRUPAL_UID") {
return 405;
}
error_page 405 = @drupal;
add_header Expires "Tue, 24 Jan 1984 08:00:00 GMT";
add_header Cache-Control "must-revalidate, post-check=0, pre-check=0";
add_header X-Header "Boost Citrus 1.9";
charset utf-8;
try_files /cache/normal/$host${uri}_$args.html /cache/$host${uri}_$args.html @drupal;
}

location @drupal {
###
### now simplified to reduce rewrites
###
rewrite ^/(.*)$ /index.php?q=$1 last;
}

location ~* (/\..*|settings\.php$|\.(htaccess|engine|inc|info|install|module|profile|pl|po|sh|.*sql|theme|tpl(\.php)?|xtmpl)$|^(Entries.*|Repository|Root|Tag|Template))$ {
deny all;
}

location ~* /files/.*\.php$ {
return 444;
}
location ~* /themes/.*\.php$ {
return 444;
}

location ~ \.php$ {
try_files $uri @drupal; #check for existence of php file
fastcgi_pass 127.0.0.1:9000; #php-fpm listening on port 9000
fastcgi_index index.php;
}

location ~ \.css$ {
if ( $request_method !~ ^(GET|HEAD)$ ) {
return 405;
}
if ($http_cookie ~ "DRUPAL_UID") {
return 405;
}
error_page 405 = @uncached;
access_log off;
expires max; #if using aggregator
add_header X-Header "Boost Citrus 2.1";
try_files /cache/perm/$host${uri}_.css /cache/$host${uri}_.css $uri =404;
}

location ~ \.js$ {
if ( $request_method !~ ^(GET|HEAD)$ ) {
return 405;
}
if ($http_cookie ~ "DRUPAL_UID") {
return 405;
}
error_page 405 = @uncached;
access_log off;
expires max; # if using aggregator
add_header X-Header "Boost Citrus 2.2";
try_files /cache/perm/$host${uri}_.js /cache/$host${uri}_.js $uri =404;
}

location ~ \.json$ {
if ( $request_method !~ ^(GET|HEAD)$ ) {
return 405;
}
if ($http_cookie ~ "DRUPAL_UID") {
return 405;
}
error_page 405 = @uncached;
access_log off;
expires max; # if using aggregator
add_header X-Header "Boost Citrus 2.3";
try_files /cache/normal/$host${uri}_.json /cache/$host${uri}_.json $uri =404;
}

location @uncached {
access_log off;
expires max; # max if using aggregator, otherwise sane expire time
}

location ~* /files/imagecache/ {
access_log off;
try_files $uri @drupal; #imagecache support - now it works
}

location ~* ^.+\.(jpg|jpeg|gif|png|ico)$ {
access_log off;
expires 30d;
try_files $uri =404;
}

location ~* \.xml$ {
if ( $request_method !~ ^(GET|HEAD)$ ) {
return 405;
}
if ($http_cookie ~ "DRUPAL_UID") {
return 405;
}
error_page 405 = @drupal;
add_header Expires "Tue, 24 Jan 1984 08:00:00 GMT";
add_header Cache-Control "must-revalidate, post-check=0, pre-check=0";
add_header X-Header "Boost Citrus 2.4";
charset utf-8;
types { }
default_type application/rss+xml;
try_files /cache/normal/$host${uri}_.xml /cache/normal/$host${uri}_.html /cache/$host${uri}_.xml $uri @drupal;
}

location ~* /feed$ {
if ( $request_method !~ ^(GET|HEAD)$ ) {
return 405;
}
if ($http_cookie ~ "DRUPAL_UID") {
return 405;
}
error_page 405 = @drupal;
add_header Expires "Tue, 24 Jan 1984 08:00:00 GMT";
add_header Cache-Control "must-revalidate, post-check=0, pre-check=0";
add_header X-Header "Boost Citrus 2.5";
charset utf-8;
types { }
default_type application/rss+xml;
try_files /cache/normal/$host${uri}_.xml /cache/normal/$host${uri}_.html /cache/$host${uri}_.xml $uri @drupal;
}

} # end of server

#######################################################
### nginx.conf catch-all
#######################################################

}