26 reputation
14
bio website
location Minhang, China
age
visits member for 2 years, 8 months
seen Jun 17 '13 at 6:35

Mar
16
awarded  Notable Question
Jun
14
awarded  Scholar
Jun
14
accepted how to add iptables rules for two NICs on CentOS(act as a gateway)
Nov
23
awarded  Popular Question
Aug
9
comment How to calculate/estimate the capacity of a switch theoretically
Sorry for my poor English and the confusion. I just wonder why the designer of the shared memory architecture switches say their switch could operate with up to 5 Gb/s capacity. How they get the 5 Gb/s capacity? If it's vendor specific actually, sorry for my question.
Aug
9
awarded  Commentator
Aug
9
comment How to calculate/estimate the capacity of a switch theoretically
The backplane speed is what I mean. I expect to get some formulas or expressions whose results are 2 Gigabit/s or some other value(5 Gb/s in my case), and the parameters of formulas/expressions are related to the shared memory architecture.
Aug
9
comment How to calculate/estimate the capacity of a switch theoretically
OK. It's just about the calculation/estimation of switch capacity according to its shared memory architecture, not of some specific manufactured switch.
Aug
9
comment How to calculate/estimate the capacity of a switch theoretically
First, thanks for your reply. So how to get the backplane speed for non blade-style switches, are there some guidelines?
Aug
9
comment How to calculate/estimate the capacity of a switch theoretically
Maybe I did't make myself clear. What I want to know is the calculating of capacity(or throughput) of a switch with its design architecture, in my case is a shared memory, presenting.
Aug
9
asked How to calculate/estimate the capacity of a switch theoretically
Aug
3
comment how to add iptables rules for two NICs on CentOS(act as a gateway)
Thanks, womble. You're so kind and patient to help me out.
Aug
3
comment how to add iptables rules for two NICs on CentOS(act as a gateway)
Thanks very much. The problem is exactly what you've said. Great thanks to you.
Aug
3
awarded  Student
Aug
3
asked how to add iptables rules for two NICs on CentOS(act as a gateway)
Aug
2
comment machines of two subnets communicate through CentOS(with two NICs)
Sorry for question nesting. I have read the manual of iptables command roughly. It seems to me that the iptables -t filter -A FORWARD -i eth0 -o eth1 -j ACCEPT should works default, however it didn't. So I still couldn't get machine A,B ping each other normally. Any specific instruction? Sorry for my stupidity
Aug
2
comment machines of two subnets communicate through CentOS(with two NICs)
So sorry for reporting wrong results. Actually it doesn't work. Only machine C could ping machine A, and I have added one rule: iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE. It seems like all packets will go to the eth0, not eth1. I have not much knowledge about iptables. So any one guide me some tutorials?
Aug
2
comment machines of two subnets communicate through CentOS(with two NICs)
To womble, thanks, Now I haven't add any rules, but it works.
Jul
29
comment machines of two subnets communicate through CentOS(with two NICs)
Thanks all for your help. To womble, could you please give me the iptables rules I should add in the case of my example in the answer.
Jul
29
asked machines of two subnets communicate through CentOS(with two NICs)