Migrating N series switches to stack config

Question

Hello,

I have deployed a N1524 switch and the customer is so happy that wants to swap the existing old 48p switch connected to his N1524 with a new N1548. Of course, I am gonna stack them, so that I can profit of a 10 gigabit backbone between the two. The idea is that N1524 would be the master and N1548 its slave. It's my first time to do this.

Usually procedures documented online are about creating a new stack from scratch, but I haven't yet seen a procedure with an already running config in mind. First I would like to ask if the procedure I would like to adopt is correct. Second, I have some questions left.

CANDIDATE PROCEDURE

0. backup N1524 running config

1. upgrade FW on both switches

2. stack ports on running N1524 and reload

3. stack ports on N1548 and shutdown

4. connect SFP+ cables: considering it's just two switches, should I cross them (port 1 on switch N1524 with port 2 on switch N1548 and vice versa) or anything goes (like port 1 on switch N1524 with port 1 on switch N1548 and vice versa)?

5. power on N1548

QUESTIONS

1. is the above procedure correct? will the N1548 directly inherit config from N1524 (of course not for its own ports) or will configurations be somehow smoked?

2. will I see the stack as a single whole switch when connecting to N1524?

3. what happens if I connect to N1548 by serial cable? And by ssh, will it have a different IP? Will I see the same config as from N1524?

4. in case of DISASTER RECOVERY, say that uplink is on N1524 and that the same N1524 dies, what happens to N1548? Will it fall back to non-stack mode? May I configure a second uplink on it in advance (and how)? Would both uplinks work simultaneously or just as failover? Should I configure a double port on the load balancer acting as gateway above (Peplink 30) for two separate cables (one to N1524 and the other to N1548) or would it just be matter of shifting the uplink cable from dead N1524 to the dedicated port on N1548?

Thanks for your help in advance

Pasha

derjaegermeister · Answer

Hello Daniel,

thanks for your fruitful answer.

The KB article on setup is exactly the one I had previously read, but, as you can see, it does not answer all my questions, to which satisfaction you have provided me interesting input.

As I got it, there is no particular order of the tengigabit ports for the cables, provided the resulting topology is a ring. Right?

Also, if I have correctly understood, the N1548 will become a mere extension of the N1524 and, therefore, will sport no IP or whatsoever.

What I haven't understood is what happens to the slave switch, should the master one die. You wrote that it detaches from the stack, which is obvious. There are still unsatisfied questions:

1. Does this imply that it will have a wiped away config? Or will it still have some?

2. Will it then have an IP? Or just serial console access? Or neither? If neither, will it need to be reset?

Btw, LAG would be a fine and elegant idea, the problem is that the uplink device is a Peplink 30 load balancer, and this model does not support LAG on LAN ports.

3. is there a way, apart from LAG, to map a port on slave switch just like an existing one on the master one which activates just in case of death of master switch, as a fallback? In that case bringing connectivity back would be as easy as moving one cable e.g. from port 1/0/1 to port 2/0/1.

Thanks!

Pasha

derjaegermeister · Answer

Thank you for your interesting answer!

Actually I have zero experience with STP, so my question is: should it be supported even on the Peplink or does it suffice to have it on the switches? This, because, of course, the peplink doesn't support it too.

In case the two switches would suffice, how would you configure the two ports on them?

Thanks

Pasha

derjaegermeister · Answer

Thanks,

I had already went though that man page, and not only the STP is only within a VPN WAN only scope, but, in any case, available only on higher models and not on Peplink 30.

But I think you gave me the right clue about ip policy route-map, looks like we're on the right path to make things work! Now, the vlan that talks with uplink is vlan 255 over a single port on N1524. When the N1548 will be stacked, besides allocating another port to vlan 255 on it, should I set the "ip policy route-map" over just the vlan or specifying ports or what?

Could you make a syntax example for this situation? Say ports are current 1/0/1 and future 2/0/1.

Thank you very much :)

Pasha

derjaegermeister · Answer

Thank you, I will use this approach. Have a nice day!

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Migrating N series switches to stack config

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