Hi,
1° Do you agree with the switches choice ?
Cisco switches are obviously capable of pretty much everything you need a switch to do, so this boils down to personal preference. For instance, I like JunOS better than IOS...
2° Can I do ethernet bonding (server side) while connecting to 2 differents switches ?
Yes.
3° If there is a problem on the path between a server and the master firewall (for example, port down on the switch), assuming that I set up arp_ip_target and arp_interval optionsof the bonding module, will the server start using its other interface to get another path ?
Linux Bonding will switch the active interface even without the arp options, when the link goes down.
4° If one interface becomes down on the server, it will start using the other one. In that case, I guess that the kernel will send a broadcast gratuitous ARP, will other Linux Kernel in the sameVLAN take that into account ?
AFAIK, yes.
5° What do you think about the switch choice, any suggestion ?
How is this different from Question 1?
6° Generally speaking, is Linux taking Gratuitous ARP into accout ? I'v got 2 cases where the kernel should send Gratuitous ARP : VRRP master change (firewall) and active interface change (ethernet bonding on server). In those cases, will Linux send gratuitous ARP and will other kernel take those packets into account ?
Generally speaking, you can get Linux to do all sorts of things if you know the right sysctl parameters.
Regards, Michael