Web and Unmanaged
Showing results for 
Search instead for 
Did you mean: 

Problem Connecting a HP1800-24G to a HP1800-8G

Go to solution
Occasional Visitor

Problem Connecting a HP1800-24G to a HP1800-8G

I have a local HP1800-24G switch that I am trying to connect to a remote HP1800-8G switch.   I would have thought connecting a single cable between the two would be the answer but it is not working for me.

 I have set both switches to factory defaults except for the IP addresses.. When I install the cable the link light flashes off and on indicating they are having a hard time making the connection.   When they finally do make a connection the link light is flashing very rapidly.  A check of the port statistics on the local 24G indicates that the port is set to 1000FDX and that there is very little packet traffic. There is however a constantly increasing amount of transmitted octet traffic being reported with very few octets being received.   All the time this is occurring I cannot access the remote switch (8G) via the web interface and I cannot ping any of the devices connected to the remote switch. 

 If I manually set the port on the 24G to 10HDX I can communicate with the remote switch via the web interface and I can ping devices connected to the remote switch but the transmitting octet traffic, although slower, is still present.

 Everything I find in the manuals or on-line talks about connecting switches using multiple ports to increase bandwidth but there is only one CAT5E line going to the remote switch and to be honest, with only 8 ports total on the remote switch I would not want to tie up another port even if there was another line.

I have a feeling I am missing something obvious but I have no idea what even after spending several hours trying to figure out what I am doing wrong.


Honored Contributor

Re: Problem Connecting a HP1800-24G to a HP1800-8G

Hi! start with the physical level:

Was/Is that Cat. 5E cable (so made for 100 Mbps / Fast Ethernet not for 1000 Mbps / Gigabit Ethernet) certified end-to-end with an instrument (RJ45 connectors, cable pairs connection scheme and cable lenght are then OK)?

If the Cat. 5E cable is just a long pre-fabricated patch cord "n" meters long you can presume it is certified at origin but doing a check wouldn't be a bad idea.

Then if you connect an host (a desktop or a notebook) on that cable directly on one of its ends (remote or local, no matter), so involving just one switch (8 ports or 24 ports), how the traffic flow behaves (did you test with iperf for verifying host-to-host connection speeds and with ping for verifying ping responses delay time or packets loss rate) against that switch and its connected hosts?

If you invert the test does something change? ...this to exclude an issue on a specific Switch if the cable has proved to be really OK.

If you're experiencing issues with just one uplink cable (which is not technically a Trunk, just an Uplink) between your two switches then aggregating (trunking) more physical ports to form a single logical Trunk is not the solution to your current issue (even if you find/have other intra-Switches free cables to use for that).

Edit: maybe this thread should be moved to "ProCurve / ProVision-Based" or "Web and Unmanaged" sub-category since the HP ProCurve 1800 Switch series (members: 8 ports J9029A - firmware PA.03.10 of 12/2013 - and 24 ports J9028A/B - latest firmware PB.03.10 of 12/2013) historically should belong to ProCurve and its switches are web manageable.

Occasional Visitor

Re: Problem Connecting a HP1800-24G to a HP1800-8G

Sorry it has taken so long to get back to you.   Since it worked at 100 FDX it went to the bottom of my list of problems to solve.   I did however find time to look at it earlier this week and your thoughts were right on the money.  It still did not work at 1000 FDX between a PC and the 24 port switch on a known good port.   I replaced the connectors twice at each end of the cable with no improvment so I finally bit the bullet and snaked another cable.  The new cable worked right out of the gate with the first connectors that I attached.   Thanks for your help.

As an aside, I am not sure what is up with this site but it would not let me login and when I asked for a new password it said the email address was good but I never received a new password even after 24 hours.  After several attempts with the same result, I finally gave up and registered with a different email address and username.






Honored Contributor

Re: Problem Connecting a HP1800-24G to a HP1800-8G

I'm glad you were able to sort it out! Thanks for the given Kudos.