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Unable to create alias in same subnetwork   ________________________________________________________________________ Applicable Environment ________________________________________________________________________ Topic: io-pkt, ifconfig alias parameter SDP: 7.1.0, 7.0.0 Target: All supported targets ________________________________________________________________________ Issue ________________________________________________________________________ In SDP 7.0/7.1, there is currently a known issue with creating an alias within the same subnetwork (Ref# J2670265). For example, below is the output of ifconfig from a QNX 7.0 VM: lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 33136 inet 127.0.0.1 netmask 0xff000000 inet6 ::1 prefixlen 128 inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1 vx0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500 capabilities rx=1f<IP4CSUM,TCP4CSUM,UDP4CSUM,TCP6CSUM,UDP6CSUM> capabilities tx=7e<TCP4CSUM,UDP4CSUM,TCP6CSUM,UDP6CSUM,TSO4,TSO6> enabled rx=1f<IP4CSUM,TCP4CSUM,UDP4CSUM,TCP6CSUM,UDP6CSUM> enabled tx=7e<TCP4CSUM,UDP4CSUM,TCP6CSUM,UDP6CSUM,TSO4,TSO6> address: 00:0c:29:89:ba:cd media: Ethernet autoselect status: active inet 192.168.36.129 netmask 0xffffff00 broadcast 192.168.36.255 inet6 fe80::20c:29ff:fe89:bacd%vx0 prefixlen 64 scopeid 0x11 If you try to add an alias within the same subnet, it will result in the following error: # ifconfig vx0 alias 192.168.191.130/24 ifconfig: SIOCAIFADDR: File exists ________________________________________________________________________ Recommendation ________________________________________________________________________ There are two workarounds recommended to mitigate this issue: 1. Add a host specific subnet route, using the netmask /32, i.e.: # ifconfig fec0 alias 128.0.2.192 netmask 255.255.255.255 Once the ip address is assigned, you should be able to ping the second ip address. 2. Delete the route for the subnet, then you can add the alias successfully, for example: a. Try adding the alias: # ifconfig wm0 alias 192.168.191.130/24 ifconfig: SIOCAIFADDR: File exists b. Delete the route for the subnet: # route delete 192.168.191.0/24 delete net 192.168.191.0 c. You can then add the alias successfully: # ifconfig wm0 alias 192.168.191.130/24 Please review the two attached documents, which provides details on the verification of the steps above. ________________________________________________________________________ NOTE: This entry has been validated against the SDP version listed above. Use caution when considering this advice for any other SDP version. For supported releases, please reach out to QNX Technical Support if you have any questions/concerns. ________________________________________________________________________ Related Attachments   Attachment Name   Size   Last Modified   alias_example_w1.txt   4KB   3/15/2024 1:41 PM   alias_example_w2.txt   4KB   3/15/2024 1:41 PM

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