Managed Switch Allowing Only IP Addresses But Not Hostnames?

[darkarn]

Hi guys, I managed to get a managed switch recently (TL-SG2008) and have connected a laptop, an AIO printer and another 3 computers to it.

There are no Internet connection problems and the computers are showing up in my router (Asus AC66U), but I realised that I can only access them via IP addresses unlike before when I was using a non-managed switch.

For example, I have a computer "ABC" with a Samba share "DEF". I used to be able to access it using "\\abc\def" but now it shows as disconnected; I need to access it as "\\192.168.1.xxx\def". Its GUI (being a headless NAS) can be accessed only with "192.168.1.xxx" instead of "abc.local"; this was not the case before today.

Similarly, when I am using apps on my mobile devices that connect them to my computers (e.g. Photosync), my computers are no longer automatically detected and showing their hostnames; I need to type in the required IP addresses to connect the devices .

I think the managed switch is the one at fault (missing DNS/DHCP packets?) What should I try?

 

[abailey]

Did you get this switch used, or have you changed a bunch of settings? My suggestion would be to do a factory reset on it and go from there.

 

[darkarn]

Did you get this switch used, or have you changed a bunch of settings? My suggestion would be to do a factory reset on it and go from there.

I got it new; have already tried resetting it before but will do that again in a while.

EDIT: Already reset but still no go...

 

[System Error Message]

Sounds like a name issue. Make sure your workgroup settings are correct and working.

It could also be that it is trying to resolve the name as a DNS in which case a little hijacking from the router and configuring the DNS server on the router can help but you would need RMerlin's firmware as you will have to use IPTables to hijack DNS(you can see my mikrotik configuration example on how). Google chrome is one example that will always use google DNS regardless of your settings(the reason is being google and bypassing DNS hacks incase your PC or router gets hacked). I also see both microsoft products and apple products doing the same thing by trying to use their own servers and not following your network settings. What i see a windows phone doing from my router is really suspicious.

by hijacking DNS traffic you can ensure that all devices in your network use the naming scheme that you set out.

This is if you cant get workgroup settings in windows to work since even i have the same issues so i dont bother with workgroup settings as i have a mixed environment.

 

[darkarn]

Sounds like a name issue. Make sure your workgroup settings are correct and working.

It could also be that it is trying to resolve the name as a DNS in which case a little hijacking from the router and configuring the DNS server on the router can help but you would need RMerlin's firmware as you will have to use IPTables to hijack DNS(you can see my mikrotik configuration example on how). Google chrome is one example that will always use google DNS regardless of your settings(the reason is being google and bypassing DNS hacks incase your PC or router gets hacked). I also see both microsoft products and apple products doing the same thing by trying to use their own servers and not following your network settings. What i see a windows phone doing from my router is really suspicious.

by hijacking DNS traffic you can ensure that all devices in your network use the naming scheme that you set out.

This is if you cant get workgroup settings in windows to work since even i have the same issues so i dont bother with workgroup settings as i have a mixed environment.

Hmm... One of the computers is running a Debian distro, does that make my environment a mixed one too (and therefore the problem lies elsewhere other than workgroup settings)?

I am leaning more towards the DNS server explanation; I am already using Merlin though. Am I right to also say that I need to do something beyond the GUI for the router and the switch?

 

[System Error Message]

IPTables on RMerlin is done through console or by editing some network file (search the asus subforum here for more details).

For the redirection to work you do need a DNS server which not all routers have.

 

[darkarn]

IPTables on RMerlin is done through console or by editing some network file (search the asus subforum here for more details).

For the redirection to work you do need a DNS server which not all routers have.

Hmm I am getting a bit confused based on what I am reading here and online; am I supposed to redirect such that the router and switch (and any other future network devices with their DNS servers) will no longer redirect based on their own instructions but based on mine?

I am still curious why this issue is occurring on a managed switch instead on unmanaged switch (was using a 3com switch before this) too

 

[System Error Message]

no, the redirection is only for DNS so you dont have to use IP addresses and you can use names again. This has nothing to do with the switch, only with gateways.

All the redirection does is send all DNS traffic to the server you specify.

 

[darkarn]

no, the redirection is only for DNS so you dont have to use IP addresses and you can use names again. This has nothing to do with the switch, only with gateways.

All the redirection does is send all DNS traffic to the server you specify.

So all I need to do is to redirect the DNS traffic to my router since that is where the DHCP server is?

Out of curiousity, I changed the DNS server on my main Windows computer and that Debian computer, unsurprisingly it did not resolve this issue...

 

[System Error Message]

aside from redirecting you also have to configure your DNS server with static names for it to work.

 

[darkarn]

aside from redirecting you also have to configure your DNS server with static names for it to work.

Hmm, something like here? http://www.snbforums.com/threads/using-rt-n66u-as-local-dns-server.12481/

Also, changing my DNS server on the Windows computer and the Debian computer to point to my router (which is also the DHCP server that also gives static IPs to all devices in my home network) cause them to show up on the DHCP Leases list in the GUI of my Asus router; any other devices connected to the switch are still not showing up in that list despite being connected to the network (e.g. the printer). I think this may help me in understanding why I need to do all these redirection?

 

[abailey]

I am confused as to why you are making any changes in configuration. Your first post said everything works fine with an unmanaged switch. If you have changed nothing else in your network and things stop working when you put in a new switch, then that is where I would be looking.

 

[darkarn]

I am confused as to why you are making any changes in configuration. Your first post said everything works fine with an unmanaged switch. If you have changed nothing else in your network and things stop working when you put in a new switch, then that is where I would be looking.

I am already looking there and still am not sure what else I can change there to resolve this (am learning a lot more about network than before though. Somewhat a good thing).

 

[System Error Message]

It is possible that you have port isolation or similar on your switch or some security setting that stops it working but using DNS hijacking and static entries in your DNS server is an alternative.

 

[darkarn]

It is possible that you have port isolation or similar on your switch or some security setting that stops it working but using DNS hijacking and static entries in your DNS server is an alternative.

I checked for that and confirmed that there is no port isolation.

I have also reset the switch again and cleared all configuration as well on it... and the problem went away! When I checked all settings and recalled what I have seen before the reset, I realised the only change is the "DoS Defend" section; right now it is disabled unlike before. I am not sure if that is relevant to this issue though...

 

[sfx2000]

A managed switch is not a router or DHCP server - so check your settings on the switch - you might have clients VLAN'ed out of scope of the DHCP server...

 

[darkarn]

A managed switch is not a router or DHCP server - so check your settings on the switch - you might have clients VLAN'ed out of scope of the DHCP server...

The VLAN options before and after the reset are the same so I don't think that happened. How does that happen anyway?