The existing network structure of our vessel when i get onboard is detailed below:
/---- Bridge Switch SRW2024P (SW2)
|
VSAT CDM570 5-Port LinkSys |-----Level4 Swtich SRW2024P (SW3)
Antenna ------ Satellite ------ CISCO 2811 ------- Unmanaged ------- Barracuda ------- SRW2024P ----- |
Controller Modem Router (1) Switch (2) Web Filter 310 Switch |-----Level2 Switch SRW2024P (SW4)
(SW0) (SW1) |
\-----Main Deck Switch SRW2024P (SW5)
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512Kbps downlink and uplink.
60+ concurrent connections during peak hours
The first thing that catched my attention was the 5-port Unmanaged Switch. According to the offsigning IT, this device is for IT-related use, specifically to bypass the firewall, such as plugging-in a laptop for downloading of drivers, etc.
As per monitoring, the performance of internet access during office hours is quite good, except during peak hours 6pm to 10pm where all crew are on online. During this period, the speed of internet for both WIFI and LAN is so slow that sometimes viewing of emails is compromised.
I tried to replacing the mentioned switch with spare SRW2024P (the only spare switch that we have onboard) and the performance, apparently, has no improvement. The reasons why I switch to SRW2024P are the features, it has Link Aggregate providing Fault Tolerant link between 2 switches, QoS, PoE, and other stuff. Being curious about managing a switch, I started looking for valuable information on the web on the configuration procedures and I ended up playing with the settings of LAG - Link Aggregation. I created 1 LAG for Port 1 and another for Port 2. Port 1 connects to CISCO2811 and Port 2 connects to Barracuda Firewall, as indicated in the diagram above. Accordingly, I found myself in the VLAN area and did some config, which I do not know if I am in the right track.
Please be informed that this is my first attempt to configure a managed switch. And other stuff are too dark for me to digest.
Finally, I saved everything and rebooted the switch. Surprisingly, the download speed showed a tremendous improvement and its really awesome that webpages are painted at once. However, there is a noticeable delay or wait state before the webpage is displayed. Apparently, the delay is in the request, and once the website has responded, the entire web page is presented pretty fast. Also, I tested the download performance using www.speedtest.net and the result is pretty bad. Before, during regular office hour, speedtest gave me 300kbps to 410kbps. But now, I have only 140 to 210Kbps. But the overall performance as of today is faster than before.
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My questions are:
1. Can anybody explain further (in layman) the operational concept of this Link Aggregate? When applied to cascading of switches, what is the best configuration?
2. In the LAG configuration, what is this Flow Control? Autonegotiation? LAG Storm Control Mode? and most especially the Threshold? I noticed that by default the Threshold is set to 64. What is the effect of setting this field to maximum (1000000)?
3. What is Trunking under VLAN. What are the benefits of setting the port as Trunking? I haven't ask for the VLAN because I do not know this stuff yet.
4. In normal switches such us SW2, SW3, SW4 & SW5, what is the best configuration for those ports where computers are connected at.
5. I spent plenty of time looking for documentation for this switch or related switches concerning DEPLOYMENT Configuration Guides, but to no avail. Where can I find such guides.
Appreciate your positive advise/comments on the above situation.
Below are the screen shuts of what I did.
