use of discontiguos-netmasks to optimize TCAM resource usage as applicable to acls

Randy randy_94108 at
Sat Jun 4 21:01:28 EDT 2016

NX-OS appears to do this:

actual acl:
show access-list v1873
IP access list v1873

10 permit ip
20 permit ip
30 permit ip
40 permit ip
50 permit ip

Same acl in TCAM:
sh system internal access-list vlan 1873 input statis
[0163:011a:011a] prec 1 permit-routed ip    [0]
[0164:011b:011b] prec 1 permit-routed ip   [0]
[0165:011c:011c] prec 1 permit-routed ip    [0]

(I don't recall this on IOS based platforms that did acl-lookups in hardware - perhaps I am wrong! May be I didn't configure an acl as the one above.)

Can someone educate me?

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