u Bu Long

Cc lnh v mngsshscppingtraceroutenmaphost

netstatiftopbwm-ngwondershaper

Lnh sshCng dng lnh ssh:Dng ng nhp vo mt my khc trn mng.M ha d liu trong qu trnh truyn i theo giao thc SSH. C php ca lnh ssh:ssh [tham s] host Cc tham s thng dng:-l: Ch nh tn ng nhp.-C: Nn tt c cc d liu trn ng truyn.

Lnh scp (Secure Copy)Lnh scp dng sao chp tp tin qua mng, d liu truyn i c m ha theo giao thc ssh.C php: scp [tham s][[user@]host1:]filename1 [...][[user@]host2:]filename2 Cc tham s-q: Khng hin th tnh trng sao chp ca tng file.-r: Sao chp cy th mc. -C:Nn file trc khi sao chp.

Lnh pingLnh ping dng :Kim tra mt my c hot ng hay khng trn h thng mng internet.Thng dng g ri khi cc vn lin quan n kt ni. C php ping: ping [tham s] hostCc tham s thng dng: -c n: Dng vic gi gi ping sau khi nhn n gi hi p. -i s: Ch nh thi gian (giy) gia mi ln gi gi ping. -R: Hin th ng i ca gi tin.

Lnh tracerouteTng t tracert trong windows command lineLnh traceroute dng :Xc nh tng bc ng i ca gi tin trong qu trnh n my ch. Gi mt gi tin UDP n mt my no . C php s dng: traceroute [-f first_ttl][-m max_ttl][-s src_addr] host Cc tham s thng dng:-f: Ch nh gi tr TTL u tin ca gi tin c gi i. -s: Ch nh a ch my ngun.-m: Ch nh gi tr TTL ln nht. -I: Cho php ta dng gi ICMP thay v UDP.

Cng c nmapDng qut kim tra IP hay cc cng trn mt my no C php:nmap [Tham s] my ch Cc tham s: -sP: Ch kim tra my ch c ang hot ng hay khng (tng t ping)-sV: Kim tra cc dch v chy trn nn UDP hay TCP, hin th phin bn ca cc dch v .-sU: Kim tra cc cng ca dch v chy UDP ang m.

Lnh hostLnh host dng :Chuyn i IP sang tn min v ngc liTng t lnh nslookupC php: host [Tham s] Tn min hay IPCc tham s chnh-R: Ch nh s ln gi yu cu truy vn. -W: Ch nh thi gian i (giy) nhn c tr li.

Lnh netstatCng dng lnh netstat:Cung cp cc thng tin nh: Tnh trng ca kt ni: Stream hay datagram Bng nh tuyn:Cha ng i ngm nh, v cc rng buc nh tuyn khc. Thng k: Cung cp cc thng tin thng k theo cc giao thc: TCP, IP, and UDP. C php:netstat [-r] [-s]

Lnh iftopLnh iftop dng gim st bng thng v cc kt ni qua cc card mngC php:iftop [i card mng] [-F net/mask]Cc tham s:-i: ch nh tn card mng m iftop s thng k bng thng s dng-F: ch nh thng tin v mng (vd: 10.0.2.0/24).

Lnh bwm-ngLnh bwm-ng dng gim st bng thng trn nhiu card mng cng lc.C php:bwm-ng [-I danh sch] [-t msec]Cc tham s chnh:-I: ch nh danh sch cc card mng cn gim st, cch nhau bi du phy.-t: khong thi gian cp nht li cc gi tr (mili giy)

wondershaperwondershaper l cng c qun l bng thng cho tng card mng trn h thng linux.Thc hin vic hn ch bng thng gi/nhn.C php:wondershaper [clear] [card mng] [tc down][tc up] Tc tnh bng kilobit/s

C ch phn quyn (tt)SetUIDSetGID

C ch phn quynTt c cc file trong linux u c cp quyn nh c, ghi, thc thi, ngoi ra cn c 2 loi quyn hn khc l SetUID v SetGIDTnh bo mt trong linux mt phn l nh vo c ch phn quyn cho User v Group.UID v GID l c ch gip linux cp quyn cho tin trnh x l hay cho tp tin.

SetUIDKhi mt chng trnh c bt SUID, bt k tin trnh no c khi to chy n u c quyn hn nh owner. Bt SUID bit bng cch:chmod u+s

SetGIDTng t vi nhm ta c SGIDBt SGID bng cchchmod g+s Ch : bo mt, hu ht cc bn linux ngy nay khng h tr trc tip SetUID v SetGID

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