Administrator Guide

Dell(conf-ext-nacl)#permit udp any any fragment
Dell(conf-ext-nacl)#deny ip any any log
Dell(conf-ext-nacl)
When conguring ACLs with the fragments keyword, be aware of the following.
When an ACL lters packets, it looks at the fragment oset (FO) to determine whether it is a fragment.
• FO = 0 means it is either the rst fragment or the packet is a non-fragment.
• FO > 0 means it is dealing with the fragments of the original packet.
Congure a Standard IP ACL
To congure an ACL, use commands in IP ACCESS LIST mode and INTERFACE mode.
For a complete list of all the commands related to IP ACLs, refer to the Dell Networking OS Command Line Interface Reference Guide. To
set up extended ACLs, refer to Congure an Extended IP ACL.
A standard IP ACL uses the source IP address as its match criterion.
1 Enter IP ACCESS LIST mode by naming a standard IP access list.
CONFIGURATION mode
ip access-list standard access-listname
2 Congure a drop or forward lter.
CONFIG-STD-NACL mode
seq sequence-number {deny | permit} {source [mask] | any | host ip-address} [count [byte]]
[order] [fragments]
NOTE
: When assigning sequence numbers to lters, keep in mind that you might need to insert a new lter. To prevent
reconguring multiple lters, assign sequence numbers in multiples of ve.
When you use the log keyword, the CP logs details about the packets that match. Depending on how many packets match the log entry
and at what rate, the CP may become busy as it has to log these packets’ details.
To view the rules of a particular ACL congured on a particular interface, use the show ip accounting access-list ACL-name
interface interface command in EXEC Privilege mode.
Examples of Using a Standard IP ACL
The following example shows viewing the rules of a specic ACL on an interface.
Dell#show ip accounting access-list ToOspf interface gig 1/6
Standard IP access list ToOspf
seq 5 deny any
seq 10 deny 10.2.0.0 /16
seq 15 deny 10.3.0.0 /16
seq 20 deny 10.4.0.0 /16
seq 25 deny 10.5.0.0 /16
seq 30 deny 10.6.0.0 /16
seq 35 deny 10.7.0.0 /16
seq 40 deny 10.8.0.0 /16
seq 45 deny 10.9.0.0 /16
seq 50 deny 10.10.0.0 /16
Dell#
The following example shows how the seq command orders the lters according to the sequence number assigned. In the example, lter
25 was congured before lter 15, but the show config command displays the lters in the correct order.
Dell(config-std-nacl)#seq 25 deny ip host 10.5.0.0 any log
Dell(config-std-nacl)#seq 15 permit tcp 10.3.0.0 /16 any
Dell(config-std-nacl)#show config
!
ip access-list standard dilling
seq 15 permit tcp 10.3.0.0/16 any
Access Control Lists (ACLs)
123