-1
votes
1answer
65 views

Filter incoming span feed to a single vlan

I have a span feed coming in on an un-addressed interface of a linux (centos) box. eth4. The span contains several vlans. I have an application which can grab packets from an interface ...
2
votes
0answers
133 views

Can ebtables BROUTING/PREROUTING package to INPUT or FORWARD table?

Can I decide the direction of package with ebtables? See the diagram above, when raw package come, I want to the package goto FORWARD table rather than INPUT table with ebtables, directly. The ...
1
vote
1answer
89 views

How to filter some protocols on all ports

Under CentOS, how can I filter traffic by protocol rather than by port? For example, I would like to filter ftp traffic regardless of the port being used in order to prevent users on the network from ...
6
votes
1answer
2k views

How to prevent IP spoofing using MAC and ebtables?

I am trying to create IP-MAC pairing rules in ebtables. There are few tutorials and related questions [1] available but I have kind of specific setting. ENVIRONMENT: I have many physical hosts. Each ...
4
votes
2answers
1k views

Server and network setup for a small private school

I help a local private school with a lot of their tech needs. So far, it's been on the order of repairing/installing office computers and helping manage the office network. But now the administrator ...
0
votes
1answer
1k views

Inconsistencies with Linux tc filter u32 matching on packet data payload - can someone explain?

I would just like some heads up on this as I really don't understand -why- this is the case. Further down is the TCPDUMP output (tcpdump -s0 -XXnni eth0 tcp port 80) of the 'HTTP' response a ...
6
votes
6answers
14k views

How does ping know that my packets are filtered?

I'm customer of an Irish ISP, eircom, which has started censoring the pirate bay. When I try to ping 194.71.107.15 which is the IP address of thepiratebay.com, I get this output: PING 194.71.107.15 ...