EMS Event "netif.tcp.conn.bad.checksum"
Applies to
- ONTAP 9.11.1 and later
- Transmission Control Protocol (TCP)
- Internet Protocol (IP)
- Networking
Issue
- Multiple
netif.tcp.conn.bad.checksum:errorevents are seen for different source and destination addresses :
[node01: kernel: netif.tcp.conn.bad.checksum:error]: TCP packet with bad checksum detected on port e0c. The packet arrived on connection with source address 10.0.0.10 and destination_address 10.0.0.1[node01: kernel: netif.tcp.conn.bad.checksum:error]: TCP packet with bad checksum detected on port e0c. The packet arrived on connection with source address 10.0.0.11 and destination_address 10.0.0.1[node01: kernel: netif.tcp.conn.bad.checksum:error]: TCP packet with bad checksum detected on port e0c. The packet arrived on connection with source address 10.0.0.12 and destination_address 10.0.0.2[node01: kernel: netif.tcp.conn.bad.checksum:error]: TCP packet with bad checksum detected on port e0c. The packet arrived on connection with source address 10.0.0.10 and destination_address 10.0.0.2<LR d="10Oct2025 04:20:09" n="node-01" t="1760037609" id="1749258895/33018" p="3" s="Ok" o="kernel" vf="" type="0" seq="270937" >
<netif_tcp_conn_bad_checksum_1
local_port="e0f"
source_address="10.63.255.1X"
destination_address="10.63.255.2X"/>
Note: The source address is usually a client address. The destination address is the Network Interface (LIF) address of the node
Bad TCP cksumis also incrementing on the port in the ifstats of the node::> system node run -node node_name -command ifstat port_name:
-- interface e0c (40 days, 5 hours, 34 minutes, 37 seconds) --
RECEIVE
Total frames: 2047m | Frames/second: 589 | Total bytes: 2625g
Bytes/second: 755k | Total errors: 0 | Errors/minute: 0
...
LRO bytes: 2527g | LRO6 segments: 0 | LRO6 bytes: 0
Bad UDP cksum: 0 | Bad UDP6 cksum: 0 | Bad TCP cksum: 21
Bad TCP6 cksum: 0 | Mcast v6 solicit: 0 | Lagg errors: 0
...
- No
CRC errorsare reported inifstat - Correct MTU is set on all interfaces (storage, switch, host)