Yesterday night we installed 2 powerconnect 5548 with a redundant power supply. The are connected stacked with HDMI cables.
We hooked up te network and then the problems started.
Very slow connections and drops in ping results.
Result was that we had a very, very slow connection with our oracle server.
After a half a hour search, I disconnected the HDMI stack cable and connected them with a patch cable.
Result, fast good connections.
Has anybody any Idea what this can be the problem?
Yes, we had the exact problem trying to stack five 5548 switches from Dell and could not figure out the problem. The network did not work well or at all. We reconnected them with patch cables and they work. Still looking for a solution myself.
The system supports up to eight units with two fixed HDMI stacking ports. The HDMI ports are 1.3a specification, Category 2 High Speed cables, 340MHz (10.2 Gbit/s). 3 meter is the maximum length supported for stacking HDMI.
It may be an incompatibility with the cable itself.
PowerConnect 5500 series switches use two HDMI 10G ports for stacking.
Also, how are you physically connecting the cables?
To connect the units in the stack:
1 Insert one end of an HDMI cable into the left-hand HDMI port on the unit at the top of the stack and the other end into the right-hand HDMI port of the unit immediately below it (this is called crossover).
2 Repeat this process until all units are connected.
3 (Optional) Connect the left-hand HDMI port of the unit at the bottom of the stack to the right-hand HDMI port of the unit at the top of the stack. This step provides increased bandwidth and redundancy.
Here is the User Guide. Stacking is discussed on page 45.
Is there any way to tell if the HDMI cable is the issue besides poor performance? Any logs or error counts? The cables do meet these specs and are 1 ft long.
After spending hours on the phone with Dell, they insisted that the problem was the cables, even through our cables conformed to the specs required. Their solution was to purchase the Dell HDMI cables and connect that way. We're not convinced, though we did get one Dell HDMI cable but have not tried it yet. One of the major limitations of these switches is apparently an inability to see errors on the HDMI interfaces, something Dell should resolve with a firmware update. An incrementing error counter would convince us the HDMI cables are the issue.
I have the same problem, just for information: My HDMI CABLES came with the switches, I have 6 switches in stack witth the cables.
After read this topic, I'm going to my datacenter change for path cables.
I saw in the latest release notes they are now recommending HDMI spec 1.4 for the cables. I do not have any of these switches, but am considering purchasing some.
Update of the firmware solved my problem. One of the problems solved, now I have another question. The LAG between 7048 and 5548 is too slow, transfer rate is 120kb - 800kb(when no one else is connected to lan). Anyone have this issue?
PS: Sorry for my english. I'm brazilian.