New ARP entries is not learned on X480

[Richard_Wenners]

We had a strange issue yesterday. One of our Summit X480 (with VIM2-10G4X card) didn't learned new ARP entries. When I tried to pinged the IPs (which has not learned) from the X480 I got error message "Packet transmit error" . A few houres earlier a got the following message in the logfile: " IPv4 multicast entry not added. Hardware L3 Table full."

After a reboot, it started to work again.

show iparp
Dynamic Entries : 7655 Static Entries : 0
Pending Entries : 10
In Request : 4631721337 In Response : 175743045
Out Request : 15168044352 Out Response : 4475702318
Failed Requests : 2508625354
Proxy Answered : 4079619495
Rx Error : 243652 Dup IP Addr : 212.37.109.1
Rejected Count : 25638473 Rejected IP : 212.112.190.157
Rejected Port : 25 Rejected I/F : VL_IN_IP-ONLY_M

Max ARP entries : 16384 Max ARP pending entries : 256
ARP address check: Enabled ARP refresh : Enabled
Timeout : 20 minutes ARP Sender-Mac Learning : Disabled
Locktime : 1000 milliseconds
Retransmit Time : 1000 milliseconds
Reachable Time : 900000 milliseconds (Auto)
Fast Convergence : Off

show iproute reserved-entries statistics
|-----In HW Route Table-----| |--In HW L3 Hash Table--|
# Used Routes # IPv4 Hosts IPv4 IPv4 IPv6 IPv4
Slot Type IPv4 IPv6 Local Remote Local Rem. Local MCast
---- --------------- ------- ------ ------ ------ ----- ----- ----- -----
1 X480-24x(10G4X) 414 0 7654 0 0 0 0 18

Theoretical maximum for each resource type:
X440 32 16 64 64 509 512 256 * 256
E4G-200 12256 6128 8189 12288 8189 8192 4096 * 6000
X460, E4G-400 12256 6128 12288 12288 16381 16384 8192 * 6000
X480(40G4X) 16352 8176 8189 16384 8189 8192 4096 * 4096
X670-48x, X670V-48x 16352 8176 8189 16384 8189 8192 4096 * 4096
X670V-48t 16352 8176 16381 16384 16381 16384 8192 * 6000
X770 16352 8176 16384 16384 131072 49152 49149 *106496
X480 262112 8192 16381 40960 16381 16384 8192 * 6000

What is the L3 host limit on a X480 with VIM2-10G4X card? Is it 8000 or 16000 host entries?

EXOS 15.5.3.4 patch1-5

[Richard_Wenners]

The output was made when we had the ARP issue. Not when the switch logged message "IPv4 multicast entry not added. Hardware L3 Table full". This message happen a few hours earlier.

Do you recommed to upgrade EXOS?

What about IGMP snooping. Why does the switch making a mcast cache when igmp snooping is disabled? Tried to disable igmp snooping on a X620 same result (the switch still making a mcast cache).

[Stephane_Grosj1]

Sorry, I didn't see the problem statement at first.
The message was pointing to a fully used HW table (L3 Hash), is the above an output at the time of the issue? Because there's no Multicast usage in it...
Maybe it's more of a bug?

[Richard_Wenners]

Hi

After the reboot everything seems to works. If the limit is 16000 L3 hosts the number of ARPs isn't the problem. We have around 8000 ARP entries. I have not change the "External lookup tables" (default L2-and-L3). Are you sure that I not have to change this to "L3-only" to increase limit to 16000 entires?

I found this post https://gtacknowledge.extremenetworks.com/articles/How_To/Multicast-Entry-not-Added-Hardware-Table-F...

So I have now tried to disable IGMP snooping, maybe there was a rogue client who sent a lot of multicast streams.

The problem is that the switch still snoops multicast groups!

disable igmp snooping vlan "VL_SN_VPLS_2000"

clear igmp snooping "VL_SN_VPLS_2000"

show igmp snooping cache vlan VL_SN_VPLS_2000
Snooping/MVR Cache Timeout: 300 sec

Type Group Sender Age InVlan

snoop 224.0.0.9 92.244.217.6 22 VL_SN_VPLS_2000
Vlan Port Vid
VL_SN_VPLS_2000 29 2000

snoop 239.192.152.143 92.244.216.46 261 VL_SN_VPLS_2000
Vlan Port Vid
VL_SN_VPLS_2000 29 2000

snoop 239.192.152.143 92.244.218.238 35 VL_SN_VPLS_2000
Vlan Port Vid
VL_SN_VPLS_2000 29 2000

Multicast cache distribution:
189 entries from Snooping 0 entries from MVR 0 entries from PIM

VL_SN_VPLS_2000: Multicast cache distribution:
61 entries from Snooping 0 entries from MVR 0 entries from PIM

Total Cache Entries: 189
Total Cache Entries for VLAN VL_SN_VPLS_2000: 61

Do I have to reboot the switch for these changes to take affect?

[Stephane_Grosj1]

Hi,

it's 16K.
What is happening?