Hmm appears I may have spoken to soon. I upgaraded the other switch to 11.4r5 and the retrnamits have come back. Althought not as frequent as last time.
So the topology is two EX4200 switches (not VC) connected via an AE port which is in a routing instance on both devices.
Config looks like this:
SWITCH 1:
show configuration routing-instances Internet protocols ospf
inactive: traceoptions {
file ospf-internet-log;
flag all;
}
external-preference 200;
export mgmt-public-to-ospf;
area 0.0.0.0 {
interface ge-0/0/12.0;
interface ae0.91;
interface lo0.1 {
passive;
}
interface vlan.96 {
passive;
}
interface vlan.69 {
passive;
SWITCH2:
show configuration routing-instances Internet protocols ospf
external-preference 200;
area 0.0.0.0 {
interface ge-0/0/12.0;
interface ae0.91;
interface lo0.1 {
passive;
}
interface vlan.96 {
passive;
}
interface vlan.69 {
passive;
}
So Ae0.91 is the interfaced used for OSPF in this routing instance.
Here is the config from the interfaces:
SWITCH1:
show configuration interfaces ae0
vlan-tagging;
aggregated-ether-options {
link-speed 1g;
lacp {
active;
}
}
unit 91 {
vlan-id 91;
family inet {
address 10.255.255.45/30;
SWITCH2:
show configuration interfaces ae0
vlan-tagging;
aggregated-ether-options {
link-speed 1g;
lacp {
passive;
}
}
unit 91 {
vlan-id 91;
family inet {
address 10.255.255.46/30;
Here are the stats
SWITCH1:
show ospf statistics instance Internet
Packet type Total Last 5 seconds
Sent Received Sent Received
Hello 0 0 0 0
DbD 0 0 0 0
LSReq 0 0 0 0
LSUpdate 914 877 3 3
LSAck 709 340 2 1
DBDs retransmitted : 0, last 5 seconds : 0
LSAs flooded : 160, last 5 seconds : 0
LSAs flooded high-prio : 703, last 5 seconds : 2
LSAs retransmitted : 70, last 5 seconds : 1
LSAs transmitted to nbr: 7, last 5 seconds : 0
LSAs requested : 0, last 5 seconds : 0
LSAs acknowledged : 830, last 5 seconds : 2
Flood queue depth : 0
Total rexmit entries : 2
db summaries : 0
lsreq entries : 0
Receive errors:
None
SWITCH2:
show ospf statistics instance Internet
Packet type Total Last 5 seconds
Sent Received Sent Received
Hello 0 0 0 0
DbD 0 0 0 0
LSReq 0 0 0 0
LSUpdate 835 1067 3 4
LSAck 16 343 0 2
DBDs retransmitted : 0, last 5 seconds : 0
LSAs flooded : 4, last 5 seconds : 0
LSAs flooded high-prio : 656, last 5 seconds : 2
LSAs retransmitted : 9, last 5 seconds : 0
LSAs transmitted to nbr: 166, last 5 seconds : 1
LSAs requested : 0, last 5 seconds : 0
LSAs acknowledged : 16, last 5 seconds : 0
Flood queue depth : 0
Total rexmit entries : 1
db summaries : 0
lsreq entries : 0
Receive errors:
None
And again, 1 minute later
show ospf statistics instance Internet
Packet type Total Last 5 seconds
Sent Received Sent Received
Hello 0 0 0 0
DbD 0 0 0 0
LSReq 0 0 0 0
LSUpdate 1017 971 6 5
LSAck 788 381 4 2
DBDs retransmitted : 0, last 5 seconds : 0
LSAs flooded : 172, last 5 seconds : 1
LSAs flooded high-prio : 783, last 5 seconds : 4
LSAs retransmitted : 79, last 5 seconds : 1
LSAs transmitted to nbr: 9, last 5 seconds : 0
LSAs requested : 0, last 5 seconds : 0
LSAs acknowledged : 916, last 5 seconds : 4
Flood queue depth : 0
Total rexmit entries : 1
db summaries : 0
lsreq entries : 0
Receive errors:
None
SWITCH2:
show ospf statistics instance Internet
Packet type Total Last 5 seconds
Sent Received Sent Received
Hello 0 0 0 0
DbD 0 0 0 0
LSReq 0 0 0 0
LSUpdate 906 1163 3 4
LSAck 16 376 0 1
DBDs retransmitted : 0, last 5 seconds : 0
LSAs flooded : 4, last 5 seconds : 0
LSAs flooded high-prio : 710, last 5 seconds : 2
LSAs retransmitted : 9, last 5 seconds : 0
LSAs transmitted to nbr: 183, last 5 seconds : 1
LSAs requested : 0, last 5 seconds : 0
LSAs acknowledged : 16, last 5 seconds : 0
Flood queue depth : 0
Total rexmit entries : 1
db summaries : 0
lsreq entries : 0
Receive errors:
None
So it seems it's just one switch that has a much higher retransmission rate (SWITCH1)
It has got less frequent since I upgraded junos but still is happening.
However i'm not seeing any network instabilities, my route table is stable. I have no errors on the physical ports
Might log this with JTAC. I can't see any issues.
I also have OSPF running on both these switches in the global route table and I don't see any LSA retransmits there