Dear Friends, I am using HTB version 0.85 in CENTOS 4.4 and I configurated to limit bandwidth port 80 (hhtp) and 25 (smtp), but HTB don't work. Below , show files. [root at srv001 htb]# ls -la total 36 drwxrwxrwx 2 root root 4096 Set 11 21:46 . drwxr-xr-x 11 root root 4096 Set 11 00:11 .. -rw-r--r-- 1 root root 19 Fev 12 2002 eth0 -rw-r--r-- 1 root root 89 Set 11 01:01 eth0-2:10.www -rw-r--r-- 1 root root 89 Set 11 21:40 eth0-2:20.smtp -rw-r--r-- 1 root root 84 Set 11 21:45 eth0-2:30.dfl -rw-r--r-- 1 root root 89 Set 11 21:46 eth0-2:40.www-out -rw-r--r-- 1 root root 63 Set 11 00:13 eth0-2.root [root at srv001 htb]# cat eth0 DEFAULT=30 R2Q=100 [root at srv001 htb]# cat eth0-2.root # root class containing total bandwidth RATE=512kbit BURST=15k # class for outgoing WWW traffic RATE=100kbit CEIL=100kbit BURST=15k LEAF=sfq RULE=*:80 [root at srv001 htb]# cat eth0-2:30.dfl # default class for unclassified traffic RATE=1Kbit CEIL=100kbit BURST=15k LEAF=sfq [root at srv001 htb]# cat eth0-2:20.smtp # class for outgoing SMTP traffic RATE=100kbit CEIL=100kbit BURST=15k LEAF=sfq RULE=*:25 Thanks for help. Adriano