does firewall prevent botnet?

[peter]

If I have a hardware SPI firewall, does that prevent my computers from
becoming a zombie or part of a botnet? In other words, can a firewall block
commands from reaching botnets bots?

 

[Lanwench [MVP - Exchange]]

If I have a hardware SPI firewall, does that prevent my computers from
becoming a zombie or part of a botnet?

Prevent? No.

In other words, can a firewall
block commands from reaching botnets bots?

You can block outbound traffic on the device, of course - perhaps block all
LAN-->WAN traffic besides TCP 80, 443, 25, 53 and 110, to help mitigate your
risk. Depends on what you need to access.

Nothing replaces good antivirus, antimalware software, regularly patched
computers/servers, and plain old caution, note.