Getting dropped packets after upgrade
Posted: Sat May 12, 2018 11:13 pm
I've got a problem I can't explain to myself with a single WS-6-MINI switch and am hoping someone out there has a suggestion...
After replacing the core router that connects this particular switch to the internet (one Mikrotik to another), this switch has started dropping pings and SNMP monitoring of it is dropping as well (matching the ping drops). Lets call this problem switch, "Switch B". It is 2 hops away from the core router we swapped out. One hop away is "Switch A", also a WS-6-MINI - which is not experiencing any issues. There is a point to point wireless link from router to Switch A and another PtP wireless link from Switch A to Switch B. Switch B also has a much slower PtP connection back to the router that is handled via RSTP.
Here is a 30 day Ping graph of Switch B:
The green lines are packet loss. There is also a very regular pattern to the packet loss. Below is the same switch with a 2-day average, not a 30 day average:
Here is the same time frame for Switch A:
No packet loss except for the moment we swapped routers...
Now, where this confuses me more is the pings to the radios attached to Switch B are fine:
That tells me this is not a wireless issue. Nothing shows any packet loss or SNMP issues except Switch B. When I look in the logs, I do not see RSTP flapping during the packet loss periods. The switch is well within temp ratings (that is graphed as well). No firmware was upgraded on the switch. It is running 1.4.9 during this whole period.
There are a bunch of clients hanging off an AP attached to Switch B. None of them show any packet loss or issues. It is only Switch B itself but it started the moment we upgraded our router (no config changes, just a hardware change). I am seeing this behavior being reported to me from two different network management computers (PRTG and Sonar) so it is not a monitoring issue.
Any thoughts?
After replacing the core router that connects this particular switch to the internet (one Mikrotik to another), this switch has started dropping pings and SNMP monitoring of it is dropping as well (matching the ping drops). Lets call this problem switch, "Switch B". It is 2 hops away from the core router we swapped out. One hop away is "Switch A", also a WS-6-MINI - which is not experiencing any issues. There is a point to point wireless link from router to Switch A and another PtP wireless link from Switch A to Switch B. Switch B also has a much slower PtP connection back to the router that is handled via RSTP.
Here is a 30 day Ping graph of Switch B:
The green lines are packet loss. There is also a very regular pattern to the packet loss. Below is the same switch with a 2-day average, not a 30 day average:
Here is the same time frame for Switch A:
No packet loss except for the moment we swapped routers...
Now, where this confuses me more is the pings to the radios attached to Switch B are fine:
That tells me this is not a wireless issue. Nothing shows any packet loss or SNMP issues except Switch B. When I look in the logs, I do not see RSTP flapping during the packet loss periods. The switch is well within temp ratings (that is graphed as well). No firmware was upgraded on the switch. It is running 1.4.9 during this whole period.
There are a bunch of clients hanging off an AP attached to Switch B. None of them show any packet loss or issues. It is only Switch B itself but it started the moment we upgraded our router (no config changes, just a hardware change). I am seeing this behavior being reported to me from two different network management computers (PRTG and Sonar) so it is not a monitoring issue.
Any thoughts?