what would cause ip/tcp/udp checksum error

[gbcbooksmj]

our Linux Server kernel log report lot of "udp bad checksum "

now i am not sure if that means the udp packet was drop by the kernel

and i am wondering what knid of think would cause the checksum error in data in transfering stage . 

[gbcbooksmj]

would Router/Switch change ip/tcp/udp checksum values ? 

[Joseph W. Doherty]

It shouldn't for higher level of the stack, i.e. L3 and/or L4.

[Joseph W. Doherty]

Sun spots ;)

Generally bad checksums (or CRCs) will cause whatever the base data being checked to be considered corrupt and ignored.

Actually there are many things that can corrupt a data transmission. If fact, at best, transmission media generally has an expected error rate, often it's a very small/low value.

Conversely, if the error rate is higher, especially if significantly higher than what the specs call for, if should be investigated for remediation.

More information might be found here: https://en.wikipedia.org/wiki/Bit_error_rate

[gbcbooksmj]

can Router/Swtich cause the data corrupt ? 

[Joseph W. Doherty]

Yes and no.

The innards of the Router/Switch, usually not.

The interfaces of the Router/Switch, it may.

[gbcbooksmj]

or ,  how can we test the bit error rate ? 

[Joseph W. Doherty]

With a device design for such testing.

However, within Cisco devices, interface stats will often reveal media corruption errors.