Ethernet Switching
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Ethernet Switching

EX-2300 tail drop packets.

‎07-13-2020 09:51 AM

Hi,

 

We are using ex2300 as access switch, but we are constantly having problems with these switches, first, we got hit with zombie switch problem and we have upgraded to 18.2R3-S2.9, and that issue solved. compared to old juniper gears like ex2220 and ex4200 series were very stable and we are happy with that, But new line are really buggy.

 

I know the reason for tail drop packets, and these are happening off-peak hours and only one-two computers are active. I checked the computers, they are not generating bandwidth greater than 1Gbps. please help me troubleshoot the issue.

 

root@RamanattukaraCore> show interfaces ge-0/0/27 extensive
Physical interface: ge-0/0/27, Enabled, Physical link is Up
Interface index: 679, SNMP ifIndex: 541, Generation: 172
Link-level type: Ethernet, MTU: 1514, LAN-PHY mode, Link-mode: Full-duplex, Speed: Auto, BPDU Error: None, Loop Detect PDU Error: None, Ethernet-Switching Error: None, MAC-REWRITE Error: None, Loopback: Disabled,
Source filtering: Disabled, Flow control: Disabled, Auto-negotiation: Enabled, Remote fault: Online, Media type: Copper, IEEE 802.3az Energy Efficient Ethernet: Disabled, Auto-MDIX: Enabled
Device flags : Present Running
Interface flags: SNMP-Traps Internal: 0x4000
Link flags : None
CoS queues : 8 supported, 8 maximum usable queues
Hold-times : Up 0 ms, Down 0 ms
Current address: 80:7f:f8:2a:f6:6b, Hardware address: 80:7f:f8:2a:f6:6b
Last flapped : 2020-07-13 08:21:43 IST (12:55:15 ago)
Statistics last cleared: Never
Traffic statistics:
Input bytes : 3508924210 0 bps
Output bytes : 5275884790 0 bps
Input packets: 3007104 0 pps
Output packets: 10214805 0 pps
IPv6 transit statistics:
Input bytes : 0
Output bytes : 0
Input packets: 0
Output packets: 0
Input errors:
Errors: 0, Drops: 0, Framing errors: 0, Runts: 0, Policed discards: 0, L3 incompletes: 0, L2 channel errors: 0, L2 mismatch timeouts: 0, FIFO errors: 0, Resource errors: 0
Output errors:
Carrier transitions: 397, Errors: 0, Drops: 119838, Collisions: 0, Aged packets: 0, FIFO errors: 0, HS link CRC errors: 0, MTU errors: 0, Resource errors: 0
Egress queues: 8 supported, 4 in use
Queue counters: Queued packets Transmitted packets Dropped packets
0 10106106 10046187 119838
1 0 0 0
2 0 0 0
3 168615 168615 0
Queue number: Mapped forwarding classes
0 best-effort
1 expedited-forwarding
2 assured-forwarding
3 network-control
Active alarms : None
Active defects : None
PCS statistics Seconds
Bit errors 0
Errored blocks 0
Ethernet FEC statistics Errors
FEC Corrected Errors 0
FEC Uncorrected Errors 0
FEC Corrected Errors Rate 0
FEC Uncorrected Errors Rate 0
MAC statistics: Receive Transmit
Total octets 3508924210 5275884790
Total packets 3007104 10214805
Unicast packets 2995171 6616696
Broadcast packets 3887 2260910
Multicast packets 8046 1337199
CRC/Align errors 0 0
FIFO errors 0 0
MAC control frames 0 0
MAC pause frames 0 0
Oversized frames 0
Jabber frames 0
Fragment frames 0
VLAN tagged frames 0
Code violations 0
PRBS Statistics : Disabled
Autonegotiation information:
Negotiation status: Complete
Link partner:
Link mode: Full-duplex, Flow control: None, Remote fault: OK, Link partner Speed: 10 Mbps
Local resolution:
Flow control: None, Flow control tx: Disabled, Flow control rx: Disabled, Remote fault: Link OK, Local link Speed: 10 Mbps, Link mode: Full-duplex
Packet Forwarding Engine configuration:
Destination slot: 0 (0x00)
CoS information:
Direction : Output
CoS transmit queue Bandwidth Buffer Priority Limit
% bps % usec
0 best-effort 95 9500000 95 0 low none
3 network-control 5 500000 5 0 low none
Interface transmit statistics: Disabled

Logical interface ge-0/0/27.0 (Index 588) (SNMP ifIndex 589) (Generation 175)
Flags: Up SNMP-Traps 0x24024000 Encapsulation: Ethernet-Bridge
Traffic statistics:
Input bytes : 231088
Output bytes : 0
Input packets: 3646
Output packets: 0
Local statistics:
Input bytes : 231088
Output bytes : 0
Input packets: 3646
Output packets: 0
Transit statistics:
Input bytes : 0 0 bps
Output bytes : 0 0 bps
Input packets: 0 0 pps
Output packets: 0 0 pps
Protocol eth-switch, MTU: 1514, Generation: 198, Route table: 6

{master:1}
root@RamanattukaraCore>

{master:1}
root@RamanattukaraCore> show interfaces queue ge-0/0/27
Physical interface: ge-0/0/27, Enabled, Physical link is Up
Interface index: 679, SNMP ifIndex: 541
Forwarding classes: 16 supported, 4 in use
Egress queues: 8 supported, 4 in use
Queue: 0, Forwarding classes: best-effort
Queued:
Transmitted:
Packets : 10046355
Bytes : 5264498773
Tail-dropped packets : 59919
RL-dropped packets : 0
RL-dropped bytes : 0
Queue: 1, Forwarding classes: expedited-forwarding
Queued:
Transmitted:
Packets : 0
Bytes : 0
Tail-dropped packets : 0
RL-dropped packets : 0
RL-dropped bytes : 0
Queue: 2, Forwarding classes: assured-forwarding
Queued:
Transmitted:
Packets : 0
Bytes : 0
Tail-dropped packets : 0
RL-dropped packets : 0
RL-dropped bytes : 0
Queue: 3, Forwarding classes: network-control
Queued:
Transmitted:
Packets : 168626
Bytes : 11404088
Tail-dropped packets : 0
RL-dropped packets : 0
RL-dropped bytes : 0

 

Thanks,
Jsree

Please Mark My Solution Accepted if it Helped, Kudos are Appreciated too .....
5 REPLIES 5
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Ethernet Switching

Re: EX-2300 tail drop packets.

‎07-13-2020 10:14 AM

Hi Jsree,

 

Could you provide these commands ?

 

show class-of-service interface <problematic interface>

show class-of-service scheduler-hierarchy interface <problematic interface>

 show configuration class-of-service

show configuration interfaces <problematic interface>

 

Best Regards,

Mohamed

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Ethernet Switching

Re: EX-2300 tail drop packets.

‎07-13-2020 10:26 AM

Hi

 

Please see the results.

 

root@RamanattukaraCore> show class-of-service interface ge-0/0/27
Physical interface: ge-0/0/27, Index: 679
Maximum usable queues: 8, Queues in use: 4
Exclude aggregate overhead bytes: disabled
Logical interface aggregate statistics: disabled
Scheduler map: <default>, Index: 2
Congestion-notification: Disabled

Logical interface: ge-0/0/27.0, Index: 588
Object Name Type Index
Classifier ieee8021p-untrust untrust 16

{master:1}
root@RamanattukaraCore> ...cheduler-hierarchy interface ge-0/0/27
error: command is not valid on the ex2300-48t

{master:1}
root@RamanattukaraCore> ...cheduler-hierarchy interface ge-0/0/27.0
error: command is not valid on the ex2300-48t

{master:1}
root@RamanattukaraCore> show configuration class-of-service

{master:1}
root@RamanattukaraCore> show configuration interfaces ge-0/0/27
unit 0 {
family ethernet-switching {
interface-mode access;
vlan {
members EDIT-LIB-USERS;
}
}
}

 

Thanks,
Jsree

Please Mark My Solution Accepted if it Helped, Kudos are Appreciated too .....
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Ethernet Switching

Re: EX-2300 tail drop packets.

‎07-13-2020 11:51 AM

Hi Jsree,

 

I saw the outputs and it looks like the device is processing the traffic based on the default queues. i.e. There is no additional CoS configuration present in this device. Please correct me if I'm wrong.

 

I can see that "Drop" counters are increasing resulting in "Tail Drops" on that particular interface. Since you mentioned that only one computer is connected, I think it might be caused due to a sudden burst of traffic. I believe these counters aren't increasing continuously.

 

Can you try this command and let me know whether it fixes your issue? - set class-of-service shared-buffer percent 100



Thanks,
π00bm@$t€®.
Please, Mark My Solution Accepted if it Helped, Kudos are Appreciated too!!!
Ethernet Switching

Re: EX-2300 tail drop packets.

‎07-13-2020 08:52 PM

Hi Jsree,

Uou say "I checked the computers, they are not generating bandwidth greater than 1Gbps."  But if you look at the output you provided it says the link is running a 10 megabit not 1 gigabit.  Look at the following from the output you provided:

 

Link mode: Full-duplex, Flow control: None, Remote fault: OK, Link partner Speed: 10 Mbps
Local resolution:
Flow control: None, Flow control tx: Disabled, Flow control rx: Disabled, Remote fault: Link OK, Local link Speed: 10 Mbps, Link mode: Full-duplex

 

Notice how it says it operating at 10 megabit and not 1 gigabit?  Are you expecting ge-0/0/27 to be operating at 10 megabit?

Thanks,

Zach

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Ethernet Switching

Re: EX-2300 tail drop packets.

[ Edited ]
‎07-14-2020 03:06 AM

Hi,

 

Thank you for pointing me that, I will check, but all the computers we have are 1Gbps capable, I didn't notice that speed mismatch. Let me confirm all the ports which are having these drops are running at 10Mbps.

Thanks,
Jsree

Please Mark My Solution Accepted if it Helped, Kudos are Appreciated too .....
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