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Additional HP switch connectivity and vlans

Hi

We are adding a 4th switch to our network.  Not sure how best to configure.

Currently (see attached (new in red)) we have 3 connected switches:

HP 2910 L3 as core with two older v1910 and 3com 2952 switches connected via cat5.   The core switch routes traffic out to firewall.
The 2910 also has two vlans configured for data and voice.  The older switches are data only.

The new 4th switch will be in another office (c10-20m run away) and is a 2910al POE also.  We need to hook up poe phones here and desktops on vlans 20 and 1 respectively.

Main questions are:
  • Do we need two cable runs from the main 3 switches to the 4th?  i..e switch 1 to 4 and switch 3 to 4 (chain mode instead of looped?)
  • If two, can we mix the connections used to connect the switches i.e. fibre and cat5 or do they need to be the same throughout the switches e.g. cat5 only?
And if two connections do they have to be routing between the vlans e.g. vlan1 connected to vlan1 on switch 1 and 4 and vlan20 between switch 1 and 4?  Or does iprouting resolve this?

Thanks
Network.jpg
Comment
Watch Question

Commented:
You only need one link from the first switch. create a trunk port and add all vlans to this port.
create on the new switch all the vlans and also create a trunk port.

make the first switch spanningtree root with an priority of 0 and the new switch a priority of 1

Author

Commented:
See attached.  Is this what you mean?

We currently dont have any ports on any switches configured as trunk ports.

Can i ask what STP does for us here?

Also ive read we need looped not chained connectivity between the switches.  Is this correct?
Trunk-port---vlan1.jpg

Commented:
configure trunk port on the 4th switch which is connecting to other swith (trunk port) and allow specific vlans or all to allow all vlans.. what ever u want... eitehr fiber or cat 5   media...

all the best

Author

Commented:
Ok.  What does the trunk port do that the current unconfigured ports that are connecting the switches do differently?

Trunking in Cisco lingo is different to HP.

Commented:
just litte command ... or gui interphase different but same in function ....

after addint trunk port configure remaining etherports to respect to their vlan/s

all the best
SouljaSr.Net.Eng
Top Expert 2011

Commented:
@CHI-LTD

A trunk port in terms of HP is not the same as what is mentioned in the previous responses. Trunk in HP terms is a similar to an ether-channel or port-channel in Cisco term. Essentially, a trunk port to HP switches are member ports that are bundled together to make one logical port. What you are looking to do instead is just tag the the two vlans on the port(ports) connected to the main switch.

Now, I would go two routes, either connect a cable to the main switch and switch 3 for a backup layer 2 patch, or connect at least two cables to the main switch and create a  "trunk" of the two connections and then tag the vlan's on the logical port created. You will need spanning tree to prevent switch loops. It should be enabled at all times anyways.

Author

Commented:
@ Soulja So like a network card team if i was to trunk port two ports together on the switch?

I believe STP is enabled regardless (especially on the L3 2910's).

Still unsure what benefit trunking is over how we have them connected now, which is default.
SouljaSr.Net.Eng
Top Expert 2011

Commented:
The way you have your current switches connected (daisy-chained) introduces points of failure for the 3com switch. It depends on switch 2 in order to reach the main switch.  Now adding the new switch and connecting it directly to the main switch is preferred. Having a second connection to switch 3 is fine for backup and STP would block that path, until the direct connection to the main switch goes down.

The benefit of the trunk port vs the two separate paths is that you will be able to use the bandwidth of the two port trunk to the main switch vs only one path when connected to two different switches. You also have redundancy with a trunk.

Author

Commented:
So i should really have dual LACP trunk ports on each switch?
Trunk-port---vlan1-v2.jpg
SouljaSr.Net.Eng
Top Expert 2011

Commented:
That is an option. The trunk to the 3Com will be blocked by STP. The trunk to your main switch will be the active path.

Author

Commented:
I note that the two old switches (2952 and 1910 dont have stp enabled.  The 2910 does.

Author

Commented:
I dont believe LACP/Trunk is going to help here.  Will vlan20 traffic route from switch 4 to switch one if connected direct between vlan1 on both providing ip routing is enabled on the new switch?
SouljaSr.Net.Eng
Top Expert 2011

Commented:
If switch one is routing for vlan 1 and vlan 20, you don't need to enable routing on the new switch. Just add the two vlans to the new switch and tag them on the ports connecting to switch 1 and tag the vlans on the ports on switch 1 ports connecting to the new switch.
SouljaSr.Net.Eng
Top Expert 2011

Commented:
The only purpose of the LACP/TRUNK is to provide a multiport logical interface for increased bandwidth as well as redundancy. It also simplifies the STP domain. Usually alleviating the need for backup STP paths and instead creating logical point to point connections.
Distinguished Expert 2018

Commented:
Just one notice. On some HP switches STP is not running by default. Make sure before you create looping topology that STP is up and running on all involved switches.

Author

Commented:
I see the core switch has STP and the others are RSTP..
Distinguished Expert 2018

Commented:
Configure RSTP on core and make it root bridge (configure lowest STP priority on it).

Author

Commented:
It doesnt appear to have RSTP as option only RTP..

Author

Commented:
Ill come back to STP & LACP etc later

At the moment im having issues getting the vlans to route.

Core switch config:
Running configuration:

; J9148A Configuration Editor; Created on release #W.15.08.0012
; Ver #02:11.05:16
hostname "HP-E2910al-48G-PoE-"
module 1 type j9148a
mirror-port 5
power-over-ethernet pre-std-detect
qos type-of-service diff-services
sflow 1 destination 172.19.10.23
sflow 1 sampling 1-48 500
timesync sntp
sntp unicast
sntp server priority 1 87.124.126.49
sntp server priority 2 178.79.165.21
time timezone 60
ip authorized-managers 172.19.0.0 255.255.0.0 access manager
ip authorized-managers 172.16.0.0 255.255.0.0 access manager
ip authorized-managers 10.255.255.0 255.255.255.128 access manager
ip authorized-managers 192.168.2.0 255.255.255.0 access manager
ip authorized-managers 192.168.3.0 255.255.255.0 access manager
ip authorized-managers 10.255.254.0 255.255.255.128 access manager
ip authorized-managers 192.168.100.0 255.255.255.0 access manager
ip authorized-managers 192.168.200.0 255.255.255.0 access manager
ip authorized-managers 10.255.253.0 255.255.255.0 access manager
ip default-gateway 172.19.10.15
no ip icmp redirects
ip route 0.0.0.0 0.0.0.0 172.19.10.15
ip routing
interface 1
   name "to HP1910 (top)"
   no power-over-ethernet
   exit
interface 2
   name "to 3com (bottom)"
   no power-over-ethernet
   exit
interface 3
   name "to ASA 5505 fe01"
   no power-over-ethernet
   exit
interface 4
   name "Cisco_AP_172.19.3.20"
   exit
interface 5
   name "to HP2910 Ground Floor"
   exit
interface 6
   no power-over-ethernet
   exit
interface 7
   name "Shoretel E1k"
   speed-duplex 100-full
   exit
interface 8
   name "Shoretel SG90"
   speed-duplex 100-full
   exit
interface 9
   name "Shoretel SG90Bri"
   speed-duplex 100-full
   exit
interface 10
   name "chi-Oaisys"
   exit
interface 11
   name "Shoretel HQ"
   exit
interface 12
   name "Ingate"
   exit
interface 16
   name "Server Room"
   exit
interface 19
   name " Phone"
   exit
interface 21
   name " "
   exit
interface 22
   name "Meeting Room"
   exit
interface 25
   name " "
   exit
interface 31
   name " "
   exit
interface 35
   name ""
   exit
interface 37
   name "to onenet e0/1"
   exit
interface 38
   name "to cisco asa e0/0"
   exit
interface 39
   name "to juniper e0/1"
   exit
snmp-server community "public" unrestricted
snmp-server contact "IT" location "HQ"
spanning-tree
vlan 1
   name "DEFAULT_VLAN"
   no untagged 7-48
   untagged 1-6
   ip address 172.19.4.5 255.255.0.0
   exit
vlan 20
   name "Voice"
   untagged 7-12,35
   tagged 13-34,36-48
   ip address 172.16.4.5 255.255.0.0
   ip helper-address 172.19.10.30
   ip helper-address 172.19.10.31
   qos dscp 101110
   voice
   exit
vlan 50
   name "vlan50"
   untagged 37-39
   no ip address
   exit
no autorun
password manager

New switch config:
Running configuration:

; J9148A Configuration Editor; Created on release #W.15.14.0016
; Ver #06:04.18.63.ff.35.05:b6
hostname "HP2910al-48G-PoE-GroundFloor"
module 1 type j9148a
power-over-ethernet pre-std-detect ports 1-48
qos type-of-service diff-services
ip default-gateway 172.19.4.5
interface 1
   name "to port 5 on HP2910"
   exit
snmp-server community "public" unrestricted
snmp-server contact "IT" location " Ground Floor"
vlan 1
   name "DEFAULT_VLAN"
   untagged 1-48
   ip address 172.19.4.6 255.255.0.0
   exit
vlan 20
   name "VLAN20"
   tagged 33-48
   no ip address
   qos dscp 101110
   voice
   exit
spanning-tree
no autorun
password manager

Ideas why im unable to get an ip from the DHCP server for the phne in port 47 vlan20?
SouljaSr.Net.Eng
Top Expert 2011

Commented:
On the new switch.I don't see you tagging vlan 1 on any ports. I'd think it would be tagged on the interfaces that connect to the core switch. Under Vlan 20 what are the ports 33-48?  Seems like a lot of ports tagging that vlan. I assume the ports connecting to the core switch is in that range?
Distinguished Expert 2018
Commented:
interface 1
   name "to port 5 on HP2910"
Need to be configured with all vlans on both sides (this port and core port connected to it).

New switch
vlan 20
   name "VLAN20"
   tagged 1, 33-48

Core
vlan 1
   name "DEFAULT_VLAN"
   no untagged 7-48
   untagged 1-6
   ip address 172.19.4.5 255.255.0.0
   exit
vlan 20
   name "Voice"
   untagged 7-12,35
   tagged 5,13-34,36-48

Author

Commented:
ok will try.

 Does the vlan20 on new switch need an IP?

Author

Commented:
@ Soulja
Ports 33-48 are for phones/voice tagged for qos
SouljaSr.Net.Eng
Top Expert 2011

Commented:
No ip is needed for vlan 20 on the new switch. I assume you are using vlan 1 for management, so that ip is fine.

Author

Commented:
yes

Author

Commented:
@ JustInCase  

Just want to confirm this is 100% correct?  Dont want to affect production traffic..
Thanks

Author

Commented:
How about pointing port 5 from core to new switch to vlan20 port directly rather than tagging port 5?
Distinguished Expert 2018

Commented:
Since there is STP involved it may cause downtime 30-50 seconds, in the case that STP reconverge, and it may not (I don't know all switches configurations etc)
What you need is to configure on uplink to forward voice traffic.
You need both VLAN 1 and VLAN20 (for management and voice), so... you need both.

Author

Commented:
Uplink being the connection between the core and new switch?

Author

Commented:
Also what i find odd is that a phone connected to vlan20 in new switch is getting IP address from DHCP server for vlan1 scope..

Author

Commented:
Surely i need a cable from vlan20 to vlan20?

Author

Commented:
Tagged ports 1 and 5 and lost ping to 172.19.4.6 (new switch)
Distinguished Expert 2018

Commented:
Vlan1 should stay untagged on both sides, as configured above.  In configuration I added vlan 20 as tagged to already untagged vlan1 on ports. Vlan1 is your management VLAN and need to be present on uplinks.

Author

Commented:
I added the two ports as tagged and lost connectivity:

New switch
vlan 20
   name "VLAN20"
   tagged 1, 33-48

Core
vlan 1
   name "DEFAULT_VLAN"
   no untagged 7-48
   untagged 1-6
   ip address 172.19.4.5 255.255.0.0
   exit
vlan 20
   name "Voice"
   untagged 7-12,35
   tagged 5,13-34,36-48

Author

Commented:
Got there in the end.  Thanks
Now need to reconfigure the 3com and HP1910 Switches to pass tagged taffic across the switches, which is causing me issues.  I'll log a new post for that...
Thanks
Distinguished Expert 2018

Commented:
You're welcome.