Showing interface statistics with ip -s link show is useful when a Linux interface looks up but packets are still being dropped, delayed, or retried somewhere below the IP layer. The extra RX and TX counters expose whether the interface is simply carrying traffic or accumulating low-level faults that need a different troubleshooting path.
The ip -s link show output comes from the kernel's per-interface link statistics and adds RX and TX counter sections beneath the normal ip link show device summary. Those sections include bytes, packets, errors, drops, multicast traffic, and other link-layer counters, while repeating the -s flag expands the error breakdown further.
These counters are cumulative until the interface is recreated or the system is restarted, so the useful signal usually comes from comparing two samples rather than reacting to a single non-zero total. Virtual devices and different drivers can also expose slightly different behavior, but rapidly increasing errors, dropped, missed, or carrier counters are the strongest clue that the fault is below routing, firewall, or application layers.
Related: How to show interfaces with ip link
$ ip -s link show dev eth0
11: eth0@if302: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65535 qdisc noqueue state UP mode DEFAULT group default
##### snipped #####
RX: bytes packets errors dropped missed mcast
41801767 2247 0 0 0 0
TX: bytes packets errors dropped carrier collsns
60662 824 0 0 0 0
Replace eth0 with the target interface name; container or veth-backed links can show a peer suffix such as eth0@if302.
$ ip -s link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000 ##### snipped ##### 11: eth0@if302: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65535 qdisc noqueue state UP mode DEFAULT group default ##### snipped #####
This is useful when the faulty interface is not yet obvious or when several links need to be compared quickly.
$ ip -s -s link show dev eth0
11: eth0@if302: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 65535 qdisc noqueue state UP mode DEFAULT group default
##### snipped #####
RX: bytes packets errors dropped missed mcast
41676062 2847 0 0 0 0
RX errors: length crc frame fifo overrun
0 0 0 0 0
TX: bytes packets errors dropped carrier collsns
77916 1089 0 0 0 0
TX errors: aborted fifo window heartbt transns
0 0 0 0 2
The ip command accepts repeated -s flags, and each extra flag increases the amount of statistics shown.
Bytes and packets rising by themselves usually mean traffic is flowing, while rising errors, dropped, missed, or carrier counters indicate an active link-quality, queueing, or driver problem.
Increasing carrier or TX/RX error-bucket values usually point to the NIC, driver, or physical link, while clean link counters with broken connectivity usually shift the focus to IP addressing, routes, firewall rules, or upper-layer services.