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    Do I need 1 or 2 Smart Switches?

    Scheduled Pinned Locked Moved Wireless
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    • M
      mifronte
      last edited by

      Thank you for the great advice!

      The more I read up on VLAN and refresh my readings on TCP/IP the more I realized that I will just start using a managed switch as a L2 device and let pfSense handle all the routing.  I too am leaning toward the Cisco SMB SG300/350 line and operate it in L2 mode until a need arises for converting it to L3 mode.

      Looks like it is not a good time to be looking for a Cisco SMB SG300/350 switch since the SG300 stock level is low and hence prices are going up.  The SG350 are not widely available yet and so their prices are high too.

      I do have a network design question and I hope I am phrasing it correctly:

      Let's say I assign a port on a managed switch to a VLAN, but the port will be an untagged member.  Can I attach an unmanaged switch to that port so that all devices connected to the unmanaged switch will be part of the port's assigned VLAN?

      If I can reuse my unmanaged switch, I may be able to get away with just the 10-port managed switch.

      SuperMicro Atom C2758 A1SRI-2758F 16GB
      2.8.0 (amd64)

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      • jahonixJ
        jahonix
        last edited by

        @mifronte:

        Let's say I assign a port on a managed switch to a VLAN, but the port will be an untagged member.

        An untagged switch-port is pretty much exactly what an unmanaged switch is on all ports. Except you cannot assign internal belongings.
        (with limitations [CDP et al], I know, but that's not relevant here.)
        Yes, that would work. But it's not exactly a straight forward design.

        @mifronte:

        If I can reuse my unmanaged switch, I may be able to get away with just the 10-port managed switch.

        That'll hardly work. Been there, done that.
        You always need one more port. If not now then tomorrow or next month.
        Your money is spent once you buy gear. You cannot reuse it to buy bigger gear (except for selling the old one on eBay and such).
        Have a look at the SG300-20. No PoE but no fan either. Might fit your project well.

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        • dennypageD
          dennypage
          last edited by

          If you search for SG 300 advice, you will find many experienced networking folk say things like "The first thing I always do with an SG 300 is put them in layer 3 mode." Like many others, I didn't listen the first time… a painful lesson. :)

          @jahonix:

          Just a reminder that the Cisco SG-300 switches need a completely new config when the fun begins. After switching to L3 mode the old L2 config is gone. You have been warned.  ;-)

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            So what if the config is gone?  He is moving from layer 2 to 3 so why would his previous config be relevant at all?

            He can save his config, move to l3 - do the play he wants, and then move back and reload his config. No harm no foul.. Few minutes of copy of a config.

            Why would you put the device in layer 3 mode if your not going to be using layer 3??  That seems like just horrible advice from someone that has no clue to be honest..

            Yeah the price point on the older 300-10 is spiked currently, you might find better pricing on the 20 for sure.  Need to wait a few months to let magic of supply and demand work its magic ;)  When the price comes down going to get a 350 and move my 300 into my av cab..  That shitty little $40 smart I have in their while it works, I just miss being able to monitor it via snmp and all the other bells and whistles that come with the sg3xx series..

            An intelligent man is sometimes forced to be drunk to spend time with his fools
            If you get confused: Listen to the Music Play
            Please don't Chat/PM me for help, unless mod related
            SG-4860 24.11 | Lab VMs 2.8, 24.11

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            • dennypageD
              dennypage
              last edited by

              It's good advice from people with experience. I've done a few of these now, and I agree with them. There really isn't any benefit to leaving the SG 300 in mode 2. As to why it's painful, you loose basic configuration that has nothing to do with mode 2/3 like certificates, users, logging, channel groups, port identification, etc. These are things you really don't want to loose, and really shouldn't loose, in a mode switch. And no, you can't reload the prior config. You have to hand edit a new config, which requires a good knowledge of what has to be changed between the modes. And if you have certificates in the config? Ouch.

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                If you have someone that is unsure of use of the switch, the differences between layer 3 and layer 2..  I don't agree with putting it in layer 3 mode and only using it as layer 2.  You would be better off leaving it layer 2 only if that is what your learning/playing with.

                The move to layer 3 if that is what you want to do and the having to put back all your common info like users and certs or ssh keys, etc.  Would all be good practice for the new user ;)

                I don't see how home/lab use of this device be layer 2 or layer 3 moving back and forth should be that big of a deal.  If your using it in a actual production setup with a complex setup you should know how your going to use it out of the gate anyway ;)

                An intelligent man is sometimes forced to be drunk to spend time with his fools
                If you get confused: Listen to the Music Play
                Please don't Chat/PM me for help, unless mod related
                SG-4860 24.11 | Lab VMs 2.8, 24.11

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                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by

                  The problem is all your layer2 config. VLANs, tagged/untagged ports are blown out. You should be able to restore a layer 2 config to a layer 3 switch. Layer 3 to layer 2 probably not so much, but I would expect Cisco to disregard the config it doesn't understand and honor what it does. That's what you pay for.

                  I set my recently-acquired SG300 to L3 out-of-the-box for just this reason.

                  Chattanooga, Tennessee, USA
                  A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                  DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                  Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    So what if they are blown out, just put them back.. You can paste in the part of the config that is pertinent..  If your trying to restore from the gui you might have some issues?  But you can always copy and paste the good stuff from your config via the cli without issue.

                    You put it in layer 3 mode out of the box for what reason - your using it as layer 3??  Do you see a need in the future to use it as layer 3?

                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                    If you get confused: Listen to the Music Play
                    Please don't Chat/PM me for help, unless mod related
                    SG-4860 24.11 | Lab VMs 2.8, 24.11

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                    • dennypageD
                      dennypage
                      last edited by

                      You can't just paste the pertinent stuff back. It ends up being more complicated than that. And by the time you have the experience necessary to hand edit the config, you have learned enough to know that you want preserve your options and put the unit in mode 3 from the beginning. Even if you have no immediate need for layer 3 routing, there is no advantage to leaving it in mode 2.

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        Other than less overhead of something your not using..

                        I am fairly freaking sure I can past my port configs and what vlans they are in back in..  Not like the syntax of commands change for gosh sake..

                        I half mind to switch it layer 3 just to prove my point ;)

                        An intelligent man is sometimes forced to be drunk to spend time with his fools
                        If you get confused: Listen to the Music Play
                        Please don't Chat/PM me for help, unless mod related
                        SG-4860 24.11 | Lab VMs 2.8, 24.11

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                        • dennypageD
                          dennypage
                          last edited by

                          In the for what it's worth category, I installed my first SG350 (replacement for the SG300) yesterday. They have completely done away with the system mode setting. :)

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                          • jahonixJ
                            jahonix
                            last edited by

                            You wanna say it's always in L3 mode?

                            BTW: Can you tell differences between 300 and 350 series? I find them extremely hard to find on Cisco's pages…  :(

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                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              Huh?  What are you looking for on cisco?

                              http://www.cisco.com/c/en/us/products/switches/350-series-managed-switches/index.html
                              http://www.cisco.com/c/en/us/products/switches/small-business-300-series-managed-switches/index.html

                              An intelligent man is sometimes forced to be drunk to spend time with his fools
                              If you get confused: Listen to the Music Play
                              Please don't Chat/PM me for help, unless mod related
                              SG-4860 24.11 | Lab VMs 2.8, 24.11

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                              • jahonixJ
                                jahonix
                                last edited by

                                The differences between SG300 and SG350.
                                Like compare SG300-10 and SG300-20 features and technical data. I know those tables.

                                Or any other document which describes what's new in 350 series.
                                Basically I don't want to campare the complete feature sets myself, only the diffs.

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                                • dennypageD
                                  dennypage
                                  last edited by

                                  @jahonix:

                                  You wanna say it's always in L3 mode?

                                  BTW: Can you tell differences between 300 and 350 series? I find them extremely hard to find on Cisco's pages…  :(

                                  I wasn't able to find any meaningful comparison of the two series on Cisco's site either. I'm guessing that is intentional.

                                  Yes, the main unit itself is always L3. The biggest change that I've noticed is that the 350 has true IPv6 support, and actually appears to route IPv6 at "wire speed". Other things of note include double the TCAM entries (includes IPv6), sFlow support, remote SPAN support for interface or vlan mirroring, L2/L3 on a per interface basis, policy based routing, and port flap monitoring. It also purports to be truly stackable.

                                  There is a new UI. Mostly good. The built in help effectively replaces the Admin Guide and is pretty good. Couple of annoying things: it seems to ignore the idle timer settings and logs you out every two minutes (I assume this is a bug); it has a basic/advanced display mode which would be fine except that basic mode hides almost all IPv6 settings. It also has SNA (Smart Network Application) which I do not have a good use for yet.

                                  One thing that I thought was rather nice is that the 10 port version can itself be powered by upstream POE ports with pass power through to downstream ports. It can also be used as a backup power to an AC adapter. Kinda sweet.

                                  The big disappointment (for me) is that gigabit port to port latency has not improved. Still 2450ns for idle, 3200ns under load for the 10 port unit. The 28 port should offer slightly better numbers (200-300ns), but I haven't tested it yet.

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                                  • johnpozJ
                                    johnpoz LAYER 8 Global Moderator
                                    last edited by

                                    "It also purports to be truly stackable."

                                    Huh where are you seeing that you can stack it?  The SG500 series is stackable.. Maybe your thinking the 350X ?

                                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                                    If you get confused: Listen to the Music Play
                                    Please don't Chat/PM me for help, unless mod related
                                    SG-4860 24.11 | Lab VMs 2.8, 24.11

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                                    • dennypageD
                                      dennypage
                                      last edited by

                                      I'm aware that it's not in the data sheet John. It's in the UI help and in the configs. I don't have a second 350 unit to confirm or deny, hence the term "purports."

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                                      • DerelictD
                                        Derelict LAYER 8 Netgate
                                        last edited by

                                        I thought the stackable (max 4) part was the 350X.

                                        Chattanooga, Tennessee, USA
                                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator
                                          last edited by

                                          And does it have a stack port on the back of it?  How exactly are you suppose to stack it?

                                          Looking online for images of the sg350 and do not see any place that would allow to connect the stack..

                                          An intelligent man is sometimes forced to be drunk to spend time with his fools
                                          If you get confused: Listen to the Music Play
                                          Please don't Chat/PM me for help, unless mod related
                                          SG-4860 24.11 | Lab VMs 2.8, 24.11

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                                          • dennypageD
                                            dennypage
                                            last edited by

                                            Perhaps I wasn't clear enough. I only have the 10 port sg350 at this time. Stacking, if it exists on the 350, would be with the 28 or 48 port models, which I have not yet had my hands on. The admin guide directly implies that the 350 series is stackable, and stack information is kicked out in the saved configs, even for the 10 port. Of course, this may be an unintended consequence of Cisco choosing to use the same firmware in the sg350 and sg350x series. I honestly don't know. If the stackable distinction is important to you, I would recommend reaching out to Cisco. Btw, there is no separate physical stack port. According to the admin guide, the standard uplink ports are used for stacking.

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