[sdnog] سؤال عن vlan

[Nishal Goburdhan]

On 14 Jan 2017, at 13:17, mahmmoud ahmed wrote:

> وعليكم السلام عثمان
> اذا كانت كل الشبكات لها private range subnet. 
> لابد من وجود router. عشان يعمل Nating. لانو 
> cisco switch layer3. لايدعم nating at all. اما اذا لم 
> يكون هنالك router. فمن الممكن ان تستبدله 
> linux box. لكي يقوم بعمل nating. ومن ناحيه اخري 
> لابد من ان يكون هنالك default route. ل router او 
> linux box. و static route من router or linux box الي switch 
> layer 3
> اما في حاله كل الشبكات public فانت لست 
> بالحاجه الي router or linux box.
>

assuming you want to use the L3 switch for routing purposes, you might 
also want to check some of the default settings that it has.
your standard switch ships with “basic” routing functions, ie. TCAM 
carved out to support basic routing functions only (eg. see below from 
my home switch).  note the limitations on the “routed” intefaces 
(ie. what you would call a switched virtual interface, or SVI).
that is, your :
   int vlanX
     ip address Y

depending on the switch that you buy, and what the code is licenced to 
do, you can change this to different features (incl IPv6).
you can get more details using:  “show sdm prefer”;  you should see 
something like:
sw02.6rdg#sh sdm prefer
  The current template is "default" template.
  The selected template optimizes the resources in
  the switch to support this level of features for
  8 routed interfaces and 1024 VLANs.

   number of unicast mac addresses:                  4K
   number of IPv4 IGMP groups + multicast routes:    0.25K
   number of IPv4 unicast routes:                    0.875k
     number of directly-connected IPv4 hosts:        0.875k
     number of indirect IPv4 routes:                 0
   number of IPv6 multicast groups:                  0.25K
   number of IPv6 unicast routes:                    0.25K
     number of directly-connected IPv6 addresses:    0.25K
     number of indirect IPv6 unicast routes:         0
   number of IPv4 policy based routing aces:         0
   number of IPv4/MAC qos aces:                      0.375k
   number of IPv4/MAC security aces:                 0.375k
   number of IPv6 policy based routing aces:         0
   number of IPv6 qos aces:                          60
   number of IPv6 security aces:                     0.125k

you can see that “default” says that this is in the default state.  
so i only have eight (8) routed vlans.
my switch is licenced for switching only (i don’t use it to route) so 
i can’t show you more detailed stuff :-(

anyway, check out your switch, and the “sdm” options to help you 
select what’s best for you.
since this will need you to reboot your switch to make things active, at 
the same time, you probably want to enable jumbo-frames etc, to save on 
a reboot.

—n.