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Effects of mismatched MTU sizes in a communication group

Question & Answer


Question

What will be the behavioral changes when there are different MTU sizes configured in a communication group?
Mismatched MTU sizes configured in a communication group is an unsupported configuration. As per RSCT admin guide, all network interfaces attached to the same subnet over which RSCT traffic may pass must be configured to use the same MTU (maximum transmission unit) size. For more information on this, you can refer to the undermentioned link:
You can check MTU size using undermentioned command
ifconfig -a
# ifconfig -a
ens192: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.20.155.11  netmask 255.255.255.0  broadcast 172.20.155.255
        inet6 fe80::250:56ff:feb9:b0e1  prefixlen 64  scopeid 0x20<link>
        ether 00:50:56:b9:b0:e1  txqueuelen 1000  (Ethernet)
        RX packets 5643308  bytes 2019789825 (1.8 GiB)
        RX errors 0  dropped 1848  overruns 0  frame 0
        TX packets 3734521  bytes 2933511615 (2.7 GiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1  (Local Loopback)
        RX packets 796  bytes 278761 (272.2 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 796  bytes 278761 (272.2 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

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Product Synonym

TSAMP
RSCT
TSA
Tivoli

Document Information

Modified date:
11 March 2022

UID

ibm16555346