On 29-08-12 22:55, STARNES, CURTIS wrote: > We are announcing our /19 network as one block via BGP through AT&T, not > broken up into smaller announcements. > Earlier in the year I started receiving complaints that some of our client > systems were having problems connecting to different web sites. > After much troubleshooting I noticed that in every instance the xlate in our > Cisco ASA for the client's IP last octet was either a 0 or 255. > Since I am announcing our network as a /19, the subnet mask is 255.255.224.0, > that would make our network address x.x.192.0 and the broadcast x.x.223.255. > So somewhere the /24 boundary addresses were being dropped. > > Just curious if anyone else has seen this before.
Yes, actually there are people over Internet blocking all IP's ending with 0 or 255 as a kind of bogon or other old wives' tale. -- Grzegorz Janoszka